Change logo in unified framework page for 2 different companies

hello,

We have a requirement to add logo in unified framework page for 2 different companies, using same portal server.

Using url alias i can differentiate logon page and I understand changing logo in Web Resource repository will change the logo.

But I need 2 logos in Web resource repository, such that when I login using one alias logo1 is chosen and when I login using another alias logo 2 is chosen?? Has some one achieved this??

Points will be rewarded.

Thanks and Regards,
Sajith