Fasih

A T1 does not have any room to burst more than 1.54 Mbps. Are you perhaps looking at the receive rate and adding it to the send rate and getting results larger than 1.54? The T1 has capacity of 1.54 transmit and 1.54 receive simultaneously.

If this is not the issue then perhaps you can post the output of show interface at a time when the rate is over 1.54?

HTH

Rick