The GWIA has a series of switches that control its timeout settings. By decreasing the default time of the timeout cycles you might be able to slightly increase the GWIA speed. However, the timeout cycles do not place an extremely significant burden on the overall performance of the GWIA so the effect might be minimal. You should consider this option only after you have tried everything else.
For information about configuring the timeout settings in the GroupWise Admin console, see Section 30.5, Configuring the SMTP Timeout Settings. For information about configuring the settings using startup switches, see Section 34.4.9, Timeouts.