One of the most frequent cause of rants about the iPhone seems about to be solved: Cerulean Studios are working on porting their Trillian Astra cross-protocol instant messenger to Macs and to the iPhone.

Not only that, but they have also started a public alpha testing program. Yes, the application is growing rapidly, and yes, you might get lucky and get to use it soon.

Click on for a big, juicy shot and for some more details.

Trillian Astra has been in development for quite a long while. The main challenge of its creators is to create a smooth multi-platform multi-service application. It might not look all that hard, but it pretty much is, as major IM services (Yahoo!, MSN) block third party clients from fully using their services. Astra for the PC and soon Mac aims to solve these problems.

Found on Friday afternoon in an entry on the developer’s blog titled ‘One more thing’ where I was stunned to find a set of three screenshots (here they are) which revealed a good and at home looking Trillian on an iPhone’s screen.

Even though it’s a browser application, it really looks good. Cerulean Studios (the developer) state that they’ve got the contact list to work (with updating lists and status messages), and also the message windows (which looked like iChat/iPhone SMS).

I used Trillian when I was a Windows user, and was extremely happy with it. Fast, small, very skinnable and expandable, and with great functionality. Now, if there only was a Linux version of it…

Read their full blog entry on the Cerulean Blog.