Simultaneous fit limited to 128 datasets?

Hi everybody,

I try to perform a simultaneous fit based on a huge number of datasets. But it seems that RooFit can only handle 128 datasets simultaneously. Does somebody know something more specific about this fact?

The following message appears 128 times starting at #0 when I run my fit procedure. But I have way more datasets connected to the simultaneous pdf via categories.
I hope this will give a hint.

[#1] INFO:Caching -- RooAbsCachedPdf::getCache(model0324) creating new cache 0x18e95f90 with pdf bw_CONV_cb_CACHE_Obs[alpha11,alpha16,mass] for nset (mass) with code 0
[#1] INFO:NumericIntegration -- RooRealIntegral::init(bw_CONV_cb_CACHE_Obs[alpha11,alpha16,mass]_Int[mass]) using numeric integrator RooIntegrator1D to calculate Int(mass)
[#1] INFO:Fitting -- RooAbsTestStatistic::initSimMode: creating slave calculator #127 for state cat0325 (6460 dataset entries)
[#1] INFO:Eval -- RooRealVar::setRange(mass) new range named 'refrange_fft_model0325' created with bounds [66,116]

I would appreciate any help!

Thanks and cheers,