Loan calculation: what gives?

[Roberto Leibman]

I'm trying to set up a loan through the loan druid. Here are the details
I put in:

Amount 11331.00
Interest Rate 4.8%
Start Date 5/18/2004
Length: 36 months
Months Remaining: 36

The resulting formula seems to be:
pmt( 0.04800 / 12 : 36 : 11331.00 : 0 : 0 )

The druid is showing me payments of 39729.60!!!! What gives?
The same exact formula (ok, changing ; for :) in openoffice gives me the
correct number of 338.58 that I see in my loan documents and expect. Is
this a bug? Did I enter any of the information wrong?

P.S. If I try to enter 3 years instead of 36 months for Length the
program just hangs (or at least it seems to, I'll let it run a bit
longer since it does seem to be doing something to the CPU.)

Thanks for the help,

Roberto

P.S. I'm using the version packaged with Fedora Core 1: gnucash-1.8.8-1
according to rpm -q