Index: src/loadext.c
==================================================================
--- src/loadext.c
+++ src/loadext.c
@@ -413,12 +413,27 @@
 ){
   sqlite3_vfs *pVfs = db->pVfs;
   void *handle;
   int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
   char *zErrmsg = 0;
+  const char *zEntry;
+  char *zAltEntry = 0;
   void **aHandle;
   int nMsg = 300 + sqlite3Strlen30(zFile);
+  int ii;
+
+  /* Shared library endings to try if zFile cannot be loaded as written */
+  static const char *azEndings[] = {
+#if SQLITE_OS_WIN
+     "dll"   
+#elif defined(__APPLE__)
+     "dylib"
+#else
+     "so"
+#endif
+  };
+
 
   if( pzErrMsg ) *pzErrMsg = 0;
 
   /* Ticket #1863.  To avoid a creating security problems for older
   ** applications that relink against newer versions of SQLite, the
@@ -431,15 +446,21 @@
       *pzErrMsg = sqlite3_mprintf("not authorized");
     }
     return SQLITE_ERROR;
   }
 
-  if( zProc==0 ){
-    zProc = "sqlite3_extension_init";
-  }
+  zEntry = zProc ? zProc : "sqlite3_extension_init";
 
   handle = sqlite3OsDlOpen(pVfs, zFile);
+#if SQLITE_OS_UNIX || SQLITE_OS_WIN
+  for(ii=0; ii<ArraySize(azEndings) && handle==0; ii++){
+    char *zAltFile = sqlite3_mprintf("%s.%s", zFile, azEndings[ii]);
+    if( zAltFile==0 ) return SQLITE_NOMEM;
+    handle = sqlite3OsDlOpen(pVfs, zAltFile);
+    sqlite3_free(zAltFile);
+  }
+#endif
   if( handle==0 ){
     if( pzErrMsg ){
       *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg, 
@@ -448,24 +469,61 @@
       }
     }
     return SQLITE_ERROR;
   }
   xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
-                   sqlite3OsDlSym(pVfs, handle, zProc);
+                   sqlite3OsDlSym(pVfs, handle, zEntry);
+
+  /* If no entry point was specified and the default legacy
+  ** entry point name "sqlite3_extension_init" was not found, then
+  ** construct an entry point name "sqlite3_X_init" where the X is
+  ** replaced by the lowercase value of every ASCII alphabetic 
+  ** character in the filename after the last "/" upto the first ".",
+  ** and eliding the first three characters if they are "lib".  
+  ** Examples:
+  **
+  **    /usr/local/lib/libExample5.4.3.so ==>  sqlite3_example_init
+  **    C:/lib/mathfuncs.dll              ==>  sqlite3_mathfuncs_init
+  */
+  if( xInit==0 && zProc==0 ){
+    int iFile, iEntry, c;
+    int ncFile = sqlite3Strlen30(zFile);
+    zAltEntry = sqlite3_malloc(ncFile+30);
+    if( zAltEntry==0 ){
+      sqlite3OsDlClose(pVfs, handle);
+      return SQLITE_NOMEM;
+    }
+    memcpy(zAltEntry, "sqlite3_", 8);
+    for(iFile=ncFile-1; iFile>=0 && zFile[iFile]!='/'; iFile--){}
+    iFile++;
+    if( sqlite3_strnicmp(zFile+iFile, "lib", 3)==0 ) iFile += 3;
+    for(iEntry=8; (c = zFile[iFile])!=0 && c!='.'; iFile++){
+      if( sqlite3Isalpha(c) ){
+        zAltEntry[iEntry++] = (char)sqlite3UpperToLower[(unsigned)c];
+      }
+    }
+    memcpy(zAltEntry+iEntry, "_init", 6);
+    zEntry = zAltEntry;
+    xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
+                     sqlite3OsDlSym(pVfs, handle, zEntry);
+  }
   if( xInit==0 ){
     if( pzErrMsg ){
-      nMsg += sqlite3Strlen30(zProc);
+      nMsg += sqlite3Strlen30(zEntry);
       *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg,
-            "no entry point [%s] in shared library [%s]", zProc,zFile);
+            "no entry point [%s] in shared library [%s]", zEntry, zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
       }
-      sqlite3OsDlClose(pVfs, handle);
     }
+    sqlite3OsDlClose(pVfs, handle);
+    sqlite3_free(zAltEntry);
     return SQLITE_ERROR;
-  }else if( xInit(db, &zErrmsg, &sqlite3Apis) ){
+  }
+  sqlite3_free(zAltEntry);
+  if( xInit(db, &zErrmsg, &sqlite3Apis) ){
     if( pzErrMsg ){
       *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
     }
     sqlite3_free(zErrmsg);
     sqlite3OsDlClose(pVfs, handle);

Index: src/sqlite.h.in
==================================================================
--- src/sqlite.h.in
+++ src/sqlite.h.in
@@ -5015,15 +5015,24 @@
 ** CAPI3REF: Load An Extension
 **
 ** ^This interface loads an SQLite extension library from the named file.
 **
 ** ^The sqlite3_load_extension() interface attempts to load an
-** [SQLite extension] library contained in the file zFile.
+** [SQLite extension] library contained in the file zFile.  If
+** the file cannot be loaded directly, attempts are made to load
+** with various operating-system specific extensions added.
+** So for example, if "samplelib" cannot be loaded, then names like
+** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
+** be tried also.
 **
 ** ^The entry point is zProc.
-** ^zProc may be 0, in which case the name of the entry point
-** defaults to "sqlite3_extension_init".
+** ^(zProc may be 0, in which case SQLite will try to come up with an
+** entry point name on its own.  It first tries "sqlite3_extension_init".
+** If that does not work, it constructs a name "sqlite3_X_init" where the
+** X is consists of the lower-case equivalent of all ASCII alphabetic
+** characters in the filename from the last "/" to the first following
+** "." and omitting any initial "lib".)^
 ** ^The sqlite3_load_extension() interface returns
 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
 ** ^If an error occurs and pzErrMsg is not 0, then the
 ** [sqlite3_load_extension()] interface shall attempt to
 ** fill *pzErrMsg with error message text stored in memory

Index: src/sqlite3ext.h
==================================================================
--- src/sqlite3ext.h
+++ src/sqlite3ext.h
@@ -467,9 +467,18 @@
 #define sqlite3_uri_parameter          sqlite3_api->uri_parameter
 #define sqlite3_uri_vsnprintf          sqlite3_api->vsnprintf
 #define sqlite3_wal_checkpoint_v2      sqlite3_api->wal_checkpoint_v2
 #endif /* SQLITE_CORE */
 
-#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
-#define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
+#ifndef SQLITE_CORE
+  /* This case when the file really is being compiled as a loadable 
+  ** extension */
+# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
+# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;
+#else
+  /* This case when the file is being statically linked into the 
+  ** application */
+# define SQLITE_EXTENSION_INIT1     /*no-op*/
+# define SQLITE_EXTENSION_INIT2(v)  (void)v; /* unused parameter */
+#endif
 
 #endif /* _SQLITE3EXT_H_ */

Index: src/test_autoext.c
==================================================================
--- src/test_autoext.c
+++ src/test_autoext.c
@@ -13,11 +13,11 @@
 */
 #include "tcl.h"
 #include "sqlite3ext.h"
 
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
-static SQLITE_EXTENSION_INIT1
+SQLITE_EXTENSION_INIT1
 
 /*
 ** The sqr() SQL function returns the square of its input value.
 */
 static void sqrFunc(