Hi,
I reference from this post
http://www.codeproject.com/Articles/9954/Incorporating-Yahoo-Messenger-into-your-website
It alway show offline, while i'm onlining.
<a href = 'ymsgr:sendim?xuannien_nt'>
<img src="http://opi.yahoo.com/online?u=xuannien_nt&m=g&t=1" border=0>
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