I suppose the CSS for both menus interfere and therefore the text that is wider than 150px does not wrap. I suggest that you use some tool to inspect the styles. I think the best tool for that purpose is Firebug for Firefox.
If you don't manage to solve the problem, you can send me a link to your project so that I am able to investigate the issue. If you don't have a live project, you can send your theme, master pages and menu skins you are using.
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