diff --git a/db/cloner.cpp b/db/cloner.cpp
index 8dd06bd9c4e..c23a3d5f32b 100644
--- a/db/cloner.cpp
+++ b/db/cloner.cpp
@@ -234,10 +234,7 @@ namespace mongo {
                         continue;
                     }
                 }
-                if( strcmp( from_name, "local.oplog.$main" ) == 0 ) {
-                    // nothing - want to clone this one
-                } else if( strchr(from_name, '$') ) {
-                    // don't clone index namespaces -- we take care of those separately below.
+                if( ! nsDollarCheck( from_name ) ){
                     log(2) << "\t\t not cloning because has $ " << endl;
                     continue;
                 }            
diff --git a/db/pdfile.cpp b/db/pdfile.cpp
index 377162670b1..8567783d6df 100644
--- a/db/pdfile.cpp
+++ b/db/pdfile.cpp
@@ -1349,7 +1349,7 @@ namespace mongo {
     */
     DiskLoc DataFileMgr::insert(const char *ns, const void *obuf, int len, bool god, const BSONElement &writeId, bool mayAddIndex) {
         bool wouldAddIndex = false;
-        massert( 10093 , "cannot insert into reserved $ collection", god || strchr(ns, '$') == 0 || strcmp( ns, "local.oplog.$main" ) == 0 );
+        massert( 10093 , "cannot insert into reserved $ collection", god || nsDollarCheck( ns ) );
         uassert( 10094 , "invalid ns", strchr( ns , '.' ) > 0 );
         const char *sys = strstr(ns, "system.");
         if ( sys ) {
diff --git a/db/pdfile.h b/db/pdfile.h
index dd8f04997f6..5cef15bd927 100644
--- a/db/pdfile.h
+++ b/db/pdfile.h
@@ -485,5 +485,15 @@ namespace mongo {
     void ensureHaveIdIndex(const char *ns);
     
     bool dropIndexes( NamespaceDetails *d, const char *ns, const char *name, string &errmsg, BSONObjBuilder &anObjBuilder, bool maydeleteIdIndex );
+
+
+    /**
+     * @return true if ns is ok
+     */
+    inline bool nsDollarCheck( const char* ns ){
+        if ( strchr( ns , '$' ) == 0 )
+            return true;
         
+        return strcmp( ns, "local.oplog.$main" ) == 0;
+    }
 } // namespace mongo
diff --git a/dbtests/basictests.cpp b/dbtests/basictests.cpp
index babef84f86a..53911aaf481 100644
--- a/dbtests/basictests.cpp
+++ b/dbtests/basictests.cpp
@@ -364,6 +364,10 @@ namespace BasicTests {
             ASSERT( Database::validDBName( "foo" ) );
             ASSERT( ! Database::validDBName( "foo/bar" ) );
             ASSERT( ! Database::validDBName( "foo.bar" ) );
+
+            ASSERT( nsDollarCheck( "asdads" ) );
+            ASSERT( ! nsDollarCheck( "asda$ds" ) );
+            ASSERT( nsDollarCheck( "local.oplog.$main" ) );
         }
     };