Windows build fails when linking against custom designer plugin

[Zanyinj]

I have an application that uses my custom qdesigner plugin collection (it includes a custom spinbox and a custom table view). When building it in ubuntu 11.10 32bit & ubuntu 11.10 64 bit, the application builds normally.
Now I am trying to build it in a windows environment. When my shared library which uses the designer plugin collection is being built,, I get undefined references to all the functions of the custom spinbox.
I cant quite figure out why the designer widget plugins link to the plugin without any problems in ubuntu and not in windows.
How do i fix this?

On another note - I noticed there is an "object_script" argument only when I am compiling the plugin collection in windows. What is this object_script and what does it do?

I use Qt 4.7.4 in all of the mentioned operating systems.

Thank you for your help.

[Zanyinj]

The issue was solved. A QDESIGNER_WIDGET_EXPORT was missing from one of the widgets' headers and the problem had only manifested itself when linking the plugin collection in windows. Another lesson learned

I am still interested in "object_script" though.