By Kasper Jade

Published: 06:00 PM EST

Apple may be double checking the operability of its new high-end eMac, while shipments of refreshed iBook and PowerBook models are reportedly already in transit to the US.

According to sources in manufacturing and reseller channels, Apple has recently placed its 1.25GHz eMac SuperDrive model on a short-term quality hold. While most resellers have yet to receive the new desktop, those who have are being instructed not to begin selling units to customers.

In a memo to employees Apple noted that there is "no confirmed problem" with existing inventory of the new eMac, but acknowledged ongoing testing of the high-end configuration. AppleInsider can only assume that a potential issue relating to the computer's new 8X Super Drive was recently questioned.

Apple's online stores in the US and UK currently reflect a 1 to 3 day delivery estimation for the 1.25 GHz Combo Drive eMac. However, the stores estimate a 5 to 7 day and 2 to 3 week wait on the Super Drive eMac, respectively.

Meanwhile, it appears that Apple is on target to refresh its portable offerings during the first half of next week, as previously anticipated. Taiwanese distribution sources have indicated that a number of iBook and PowerBook configurations are currently in air-transit to US distributors.

Additionally, multiple sources have now confirmed a majority of the Apple product numbers listed for the new laptops in an earlier report. According to an unconfirmed tip, among the many configurations planned for release are a 12-inch 1GHz G4 iBook equipped with a 30 GB hard drive, 256 MB RAM, and a Combo Drive. The low-end 14-inch iBook model will reportedly pack a 1GHz processor, 40 GB hard drive, 256 MB RAM, and Combo Drive.

If the two entry level iBook configurations are indeed accurate, next week's product introductions will mark a milestone for Apple, as it will no longer be manufacturing a CPU unit with a clock-speed below 1GHz.

Sources said to expected the new models by Tuesday afternoon. Combo Drive 1.25GHz eMacs should begin shipping on Monday.