iSync 2.1 adds new support for a number of phones, one designated as “Motorola E398B.” It includes a new icon…

which, if you look closely, has four keys just below the screen, as compared to the actual standard E398, which only has three keys. One might say that this is merely a discrepancy in the icon, but if you compare the new E398B icon to the old E398 icon, you can clearly see that this change is deliberate.

Old E398 icon

New E398B icon

This is significant because the rumored and as yet unreleased iTunes phone—the E790—looks just like the E398, except for the fourth button. The fourth button on the rumored E790 is a hotkey for the iTunes client software.

This adds to the likelihood that the Motorola E398 may be released soon as an iTunes compatible phone, perhaps dubbed the “E398B.” I recently posted that there are some who have flashed their E398s with E790 software to make it iTunes compatible, but the hack is not for the faint of heart.

Details of how to find the icons and additional messages in the new iSync that hint to iTunes integration can be found on Macrumors.com’s message board, here.