This is a Windows problem and not Macintosh one. One more of a long list.
The first time a browser enters in a php frameset page there is no problem but the second time, with the url variable changed, the page is loaded as the first time, using the old url var. I´ve tried some things like sess vars but nothing works.
It sounds me like a cache issue because the problem persists even restaring the computer.
Thanks in advance for any suggestion.