Many of the 56k modems installed inside the recent breed of iMacs won’t deliver above 26 to 28k per second, says the San Francisco Chronicle.

Two Mac Web sites - MacInTouch and MacFixIt - have been collecting information regarding the issue, discussion also exists on Apple’s Tech Exchange support bulletin board.

Apple has cited a number of factors that could affect modem speed - bandwidth at the server, failing telephone lines - but has so far failed to confront the issue, the Chronicle reports.

The paper reports that the modem chips Apple uses to implement the V.90 standard do so in a way that is not fully compatible with other manufacturer’s implementations of the standard, particularly 3Com’s. 3Com modems are often used by ISP’s, hence the loss in connection speeds.

Though Apple, at the time of writing has not yet released a modem script to address the issue, some independent alternatives do exist. Ross Barkman, at www.taniwha.cwc.net, offers a script that claims to address this. The script has not been tried and tested by Macworld, and it’s not supported by Apple. Ideally, the Chronicle complains, Apple should address this issue itself.