You are not going to be able to reliably obfuscate a URL so that all mail clients do not see it as such without obfuscating it so far that the user will not understand it either.
You could try spacing everything out like http :// www . example . com / dir / subdir / file ? qstring
. The only other way I can think of is to include the URL as an image if you are sending rich-text mail. Both these techniques though will trip anti-spam measures as trying to disguise URLs is one of the most obvious signs of spammer activity.
1Also, embedding images is bad from accessibility point of view. Plain text can be viewed with big fonts, read aloud with voice synthesis etc. – Tadeusz A. Kadłubowski – 2009-09-03T09:57:40.337
thanks for your suggestion but that's not good enough (I guess there's no solution). I rather kept just abcd without .com. But thanks anyway. – None – 2009-09-10T16:04:15.787