Attribute Assertion value differs in Moz vs IE

Hello,

I've recently started using Selenium, and I'm thoroughly impressed.
(Good work!!)

However, I'm encountering an issue that I can't seem to resolve.

Specifically, what's happening is that I'm trying to assert an
attribute value (in this case, the source location of an image) and I
get difference behaviours when I run the test in IE 6(.0.2800) compared
with FireFox 1.0.7.

Specifically, I'm checking for a relative path in my test, and that
works fine in Firefox since a relative path is returned in the HTML.
However, running the same test in IE fails. A relative path is still
being returned in the HTML Source (viewed from IE) however.

I'd like to know if anyone can offer suggestions on how to get around
this, or whether there is a known solution...