cluster.split error

Dear Mothur Group,

I am getting following error when running the command below. I have enough space to run but still i am getting this error.

mothur > cluster.split(column=stability.trim.contigs.good.unique.good.filter.unique.precluster.pick.pick.subsample.dist,name=stability.trim.contigs.good.unique.good.filter.unique.precluster.pick.pick.subsample.names, method=average, large=f,processors=1)

Using 1 processors.
Using splitmethod distance.
Splitting the file…
[ERROR]: std::bad_alloc has occurred in the SplitMatrix class function splitDistanceRAM. This error indicates your computer is running out of memory. This is most commonly caused by trying to process a dataset too large, using multiple processors, or a file format issue. If you are running our 32bit version, your memory usage is limited to 4G. If you have more than 4G of RAM and are running a 64bit OS, using our 64bit version may resolve your issue. If you are using multiple processors, try running the command with processors=1, the more processors you use the more memory is required. Also, you may be able to reduce the size of your dataset by using the commands outlined in the Schloss SOP, http://www.mothur.org/wiki/Schloss_SOP. If you are uable to resolve the issue, please contact Pat Schloss at mothur.bugs@gmail.com, and be sure to include the mothur.logFile with your inquiry.^[[H^[[2J

How big is the distance file? Can you post the rest of the command line? Is the distance matrix really in column format?