problem with the <base href....> tag

i've a little problem with the <base> tag.
I wanted to set the base href to a directory called mysite.
So I put <BASE href="/mysite/"> in my document header.
But, when I lanched IE5, the browser didn't understood the <base>
correctly, it assumed that i wanted to put http:///green/ (I saw it
because i looked to the status bar while my mouse was over a link)
what's wrong ? does it only happens with IE5 ? How can I correct it,
please ?

Mat
www.dioxine.com/king
icq 49445666

PS: please excuse my bad and ugly english - I'm french -