Running Avast 2.0.4993 on HTC Desire HD with CyanogenMOD 10.1 SR1 Android 4.2.2 rooted.
SMS filter works fine in general.
If sender has dot symbols in name (for example “www.sl.lt”) after adding from SMS/MMS history, it will be added as “wwwsllt”. This doesn’t match the name of sender afterwards and messages get thru the filter.