The jos_vm_currency code table does not hold any information about the numeric currency code that some payment modules need.
You can find a list of the valid numeric currency codes here
http://www.iso.org/iso/en/prods-services/popstds/currencycodeslist.html
I must suggest that a new column is made to the jos_vm_currency table to hold these values if you have to use a payment module that requieres these values.