There are no reported infections from the new worms. However, F-Secure says that the new viruses fix a problem with earlier versions of Cabir that prevented that worm from spreading quickly between mobile phones.More info at PC World
"These new variants seem to be recompiled versions based on original Cabir source code. Which means that the Cabir source code is floating around in the underground. Which is bad news," the company says in a statement.
Cabir.H and Cabir.I virus spreading more quickly - mobile phone virus

New variants of the Cabir virus were detected this week which have new features allowing them to spread more quickly between vulnerable devices. Cabir.H and Cabir.I are the latest versions of a worm that attacks Symbian-based cell phones.