RMark Burnham Ananlysis

I'm currently conducting an analysis of seasonal survival in RMark using
Burnham's joint analysis model.  The year is broken into the non-breeding
season (Sept. - April) and the breeding season (May-August).  Capture
periods occur in May, June, and August, so that the breeding season is
divided into 2 intervals (mid-May to mid-June and mid-June to late August)
and the non-breeding season is a single interval from September to April.
In MARK I could go into the PIMS and 'constrain' the 2 intervals of a
breeding season to have the same survival, but I can't figure out how to do
this in RMark.  It seems that adding a factor for breeding season and
non-breeding season may be the only way to do this.  This would require a
new factor for each model of interest (e.g., nbs(.) bs(.) vs. nbs(t) bs(t))
- I wanted to see if there were other options before going further.  Any
ideas would be appreciated.

Thanks,

Jeff Warren
Wildlife Biologist
Red Rock Lakes NWR
Lima, Montana 59739
(406) 276-3536