i tink that is way much slower of what a 802.11g/b connection is expected to run. when running on the newer 11g version, you shd expect about 35mbps connection (when RF conditions are good) which is about 4.5Mbytes/s.
hence check a few things,
1. ensure that both the terminals are using the latest 802.11g to communicate. if a 11b (or 11a) device is used, the system automatically falls back to the slower connection speed.
2. check that no one is leeching on ur bandwidth by securing your wireless connection
3. RF signal is sufficiently strong