Just a quick note that while upgrading to Ubuntu 9.10 I noticed that aqbanking had some packages upgraded. I gave gnucash another try and got OFX to work with USAA. I had previously installed aqbanking-tools and I am not sure if this is installed by default with gnucash. The program versions are listed below and these are from the repositories without compiling.
gnucash 2.2.9
aqbanking-tools 4.1.2-1
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