Problem Running Blast Jobs.

I started to run blast, locally on my machine, on 4 files with 1323, 210, 501, 166 fasta sequences each.

For all jobs except the first one blast returned an error:

blastall(7004) malloc: *** mmap(size=2097152) failed (error code=12)
*** error: can't allocate region
*** set a breakpoint in malloc_error_break to debug

The first job is currently still running as I'm writing this.

The exact blastall command used is as follows:

blastall -p blastn -d /Users/anjan/blastdb/nt -i <input.filename.fasta>  -o RPMBBP10.fasta.blast.out -m 8 -b 10000.

The version of Blast is 2.2.17. I'm running this on a Mac server with 2 Quad-core Intel processors with 16GB RAM. Anyone has any ideas on what the source of the problem is?