linking problem under windows

Hi to all.
I'm developing an application that use a static library ( i'm also the developer of the lib).
This static library need to be linked with libcurl, but i've some problems to do this.

Under linux (ubuntu 9.10) the makefile has a string like this:
(note that ljacksms is the name of my static library)

g++ [various qt string] -lcurl -ljacksms

and works fine.

on windows is needed another lib:
g++ [various qt string] -lcurl -lcurldll -ljacksms

but i have many linker errors like this:
In function `name':: undefined reference to `curl_global_init'
i'm getting wrong something?

ps: yes, my english is not very good...
Thanks.

Do you get any error message before all the undefinied references like cannot find lib called something? What are the first lines of output of the linker command?