AddSubaccount()
From Rackspace Email & Apps API
This function will add a new sub-account to an existing reseller account.
Parameters
Four strings:
Administrative username, (must belong to a reseller account) Administrative password, New sub-account name,
Account number ("account")
Return Values
If successful, the return value of the function will be 1.
If successful, a new account number is generated and returned in the fourth string.
Consult the Result Code Table for a list of result codes and their meaning.