The problem is not in browser I think the problem in the certificate and where he, winxp compares the certificate name and the host, win7 of this comparison probably is not
SNI is a feature all modern browsers support. It is required for hosting multible certificates for one site. Surfing the web with windows XP is very dangerous. Update to windows7!
I use my stationary pc with wxp, only for 15-25 sites and two games, so that no surfing the web. Thank you updated certificate and specify the domain q3df.org Now on wxp work fine.