diff --git a/tests/scripts/generate_code.pl b/tests/scripts/generate_code.pl
index 49af2db..84e949d 100755
--- a/tests/scripts/generate_code.pl
+++ b/tests/scripts/generate_code.pl
@@ -256,7 +256,7 @@
             $param_defs .= "    char *param$i = params[$i];\n";
             $param_checks .= "    if( verify_string( &param$i ) != 0 ) return( DISPATCH_INVALID_TEST_DATA );\n";
             push @dispatch_params, "param$i";
-            $mapping_regex .= ":[^:\n]+";
+            $mapping_regex .= ":(?:\\\\.|[^:\n])+";
         }
         else
         {