howto enable GD extension in PHP5.2/apache 2.2.4 on windows xp?

I´m having a BIT of a problem installing opencart.
I can't get further than step1 because of gd extension not available.

I've uncommented from php.ini the line: extension=php_gd2.dll
and checked that extension dir is right with correct dll.

I've doanloaded gd dll from php 4xx package and from libgd.org.

Dunno what to next. Neither of them seems to be working. Any help guys?

Thanks!

[edit]
jees. I downloaded php5.zip and uploaded php_gd2.dll
-file to extension dir and it worked!

Thanks guys!

[/edit]

thanks to this info.