RMagick problem on Windows

Hi all,

for first sorry for my english.

I've a little problem with RMagick on Windows Vista.

I've decided to use the "Paperclip" plugin an it works fine, than I've
decided to install RMagick in order to create image thumbs but ... even
if i followed the instructions i can see an error like:

"Unable to load module ...
-c:/ruby/lib/ruby/gems/1.8/gems/rmagick-2.5.0-x86-mswin32/ext/RMagick2.so"

But the RMagick2.so exists in that directory. sad

Can somebody help me?

I'm using Rails 2.2.2 with Ruby 1.8.6

Tnx a lot.