Yamaha DTXpress/DTXplorer/DTXtreme

Hi everyone!

I have a DTXpress 1 drum kit (I know it's old but it still does the 
job) and I've purchased a DTXtreme snare drum pad (RHP120SD). Now, the 
RHP120SD has 2 triggers, the drumhead and the rim. I hooked up the 
RHP120SD to the snare input of my DTXpress brain (with is also 
supposed to be a stereo input) using a stereo cable. When I hit the 
rim, there is no rim hit triggered into the brain it is only triggered 
when I play actual rim shots very loud hitting both the rim and the 
drumhead at the same time. So my question is: Is it possible to 
configure the brain to play a crossstick sound when I play only the 
rim of my pad? If yes, how is that done? I don't really care about the 
rimshots, only crosssticks.

Thanks in advance...