UI Threads in MDI environment

Question

Hi,

I'm developing a serial terminal that supports multi sessions (A Form for every new serial opened).
My problem is when a port receives big amount of data which means that the corresponding Form should be updated all the time -> UI thread gets busy and other elements in the UI becomes slow to operate.
How can I solve this ?
The Ideal way is that every Form (or control on that Form) will be in a separate thread.
Is there a way to write multi threaded UI ?

Thanks,
adidardi