URL length too short

[turd ferguson]

I need to open URLs longer than 289 characters. Anybody know of an alternate method.

I'm currently doing

code:
mlSendToWinampStruct s={ML_TYPE_ITEMRECORDLIST,(void*)&obj,enqueue);

SendMessage(plugin.hwndLibraryParent,WM_ML_IPC,(WPARAM)&s,ML_IPC_SENDTOWINAMP);

It's the same length accepted the File > open URL command too.