Changing default Work Item type in RTC for CLM link

I have defined Rational Focal Point as a consumer of RTC. When I try to create a new Work Item in RFP there is only one Work Item type presented. I suppose this is the default Work Item in RTC. How can I change this default Work Item type? Or is it possible to choose from a list of Work Item types when I want to create a new one in RFP?