using bugpoint

I am trying to use bugpoint to reduce the bytecode for a bug in one of my transformations. Normally I run opt as such:

opt -mypass -param1 -param2 -o b.bc a.bc

Here, -mypass specifies a pass and -param1 and -param2 are just parameters that -mypass uses. I added them using the command line parsing library that llvm supports. I tried running bugpoint with the following:

bugpoint a.bc -mypass -param1 -param2

However, bugpoint always eliminates -param1 and -param2 from the list and runs into an assertion that will currently always happen if -param1 and -param2 are not specified. I have also tried to put --args -- in front of -param1 -param2 and --tool-args -- in front of -param1 -param2, and neither have helped. How do I force bugpoint to keep the -param1 and -param2?