Index: src/test_async.c
==================================================================
--- src/test_async.c
+++ src/test_async.c
@@ -619,17 +619,22 @@
       if( pIter->eAsyncLock>eRequired ){
         eRequired = pIter->eAsyncLock;
         assert(eRequired>=0 && eRequired<=SQLITE_LOCK_EXCLUSIVE);
       }
     }
+
     if( eRequired>pLock->eLock ){
       rc = sqlite3OsLock(pLock->pFile, eRequired);
-    }else if(eRequired<pLock->eLock){
+      if( rc==SQLITE_OK ){
+        pLock->eLock = eRequired;
+      }
+    }
+    else if( eRequired<pLock->eLock && eRequired<=SQLITE_LOCK_SHARED ){
       rc = sqlite3OsUnlock(pLock->pFile, eRequired);
-    }
-    if( rc==SQLITE_OK ){
-      pLock->eLock = eRequired;
+      if( rc==SQLITE_OK ){
+        pLock->eLock = eRequired;
+      }
     }
   }
 
   return rc;
 }
@@ -930,15 +935,15 @@
       }
 
       /* Replace any occurences of "<path-component>/../" with "" */
       if( iOut>0 && iIn<=(nPathOut-4) 
        && zPathOut[iIn]=='/' && zPathOut[iIn+1]=='.' 
-       && zPathOut[iIn+2]=='.' && zPathOut[iIn+2]=='/'
+       && zPathOut[iIn+2]=='.' && zPathOut[iIn+3]=='/'
       ){
         iIn += 3;
         iOut--;
-        for( ; iOut>0 && zPathOut[iOut]!='/'; iOut--);
+        for( ; iOut>0 && zPathOut[iOut-1]!='/'; iOut--);
         continue;
       }
 
       zPathOut[iOut++] = zPathOut[iIn];
     }

ADDED   test/async3.test
Index: test/async3.test
==================================================================
--- test/async3.test
+++ test/async3.test
@@ -0,0 +1,72 @@
+# 2007 September 5
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# The focus of this file is testing the code in test_async.c.
+# Specifically, it tests that the xFullPathname() method of
+# of the asynchronous vfs works correctly.
+#
+# $Id: async3.test,v 1.1 2007/09/05 14:32:25 danielk1977 Exp $
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+if { [info commands sqlite3async_enable]==""  } {
+  # The async logic is not built into this system
+  puts "Skipping async3 tests: not compiled with required features"
+  finish_test
+  return
+}
+
+db close
+sqlite3async_enable 1
+sqlite3async_start
+
+set paths {
+  chocolate/banana/vanilla/file.db
+  chocolate//banana/vanilla/file.db
+  chocolate/./banana//vanilla/file.db
+  chocolate/banana/./vanilla/file.db
+  chocolate/banana/../banana/vanilla/file.db
+  chocolate/banana/./vanilla/extra_bit/../file.db
+}
+
+do_test async3-1.0 {
+  file mkdir [file join chocolate banana vanilla]
+  file delete -force chocolate/banana/vanilla/file.db
+  file delete -force chocolate/banana/vanilla/file.db-journal
+} {}
+do_test async3-1.1 {
+  sqlite3 db chocolate/banana/vanilla/file.db
+  execsql {
+    CREATE TABLE abc(a, b, c);
+    BEGIN;
+    INSERT INTO abc VALUES(1, 2, 3);
+  }
+} {}
+
+set N 2
+foreach p $paths {
+  sqlite3 db2 $p
+  do_test async3-1.$N.1 {
+    execsql {SELECT * FROM abc} db2
+  } {}
+  do_test async3-1.$N.2 {
+    catchsql {INSERT INTO abc VALUES(4, 5, 6)} db2
+  } {1 {database is locked}}
+  db2 close
+  incr N
+}
+
+db close
+sqlite3async_halt idle
+sqlite3async_wait
+sqlite3async_enable 0
+finish_test