I find that in various situations Objective-C code in Xcode 3.1 (Leopard) can fail to get appropriate syntax coloring after typing or lose coloring that it had.

This isn't just a "refresh" issue with new custom symbols -- but affects Cocoa framework symbols as well.

Sometimes CMD-a to select all text on the code page will make the coloring (re)appear, sometimes double-clicking on a line to select it will work, sometimes I have to add/delete a space in a symbol to get that symbol to (re)color. Rebuilding, or closing/reopening the project may or may not work.

Is this a known issue with Xcode? For something so annoying to me, I'm not finding the plentiful discussions of it on SO and elsewhere I'd expect.

And is there any command to force global syntax recoloring?