diff --git a/src/compiler/api/GF/Grammar/Parser.y b/src/compiler/api/GF/Grammar/Parser.y
index 9ffc2b30a..d8a06351f 100644
--- a/src/compiler/api/GF/Grammar/Parser.y
+++ b/src/compiler/api/GF/Grammar/Parser.y
@@ -294,6 +294,9 @@ FlagDef
   : Posn Ident '=' Ident Posn  {% case parseModuleOptions ["--" ++ showIdent $2 ++ "=" ++ showIdent $4] of
                                     Ok  x   -> return x
                                     Bad msg -> failLoc $1 msg                                           } 
+  | Posn Ident '=' String Posn {% case parseModuleOptions ["--" ++ showIdent $2 ++ "=" ++ $4] of
+                                    Ok  x   -> return x
+                                    Bad msg -> failLoc $1 msg                                           } 
   | Posn Ident '=' Double Posn {% case parseModuleOptions ["--" ++ showIdent $2 ++ "=" ++ show $4] of
                                     Ok  x   -> return x
                                     Bad msg -> failLoc $1 msg                                           }