What are the differences between 4.01 and 4.44? (I mean what's new in 4.44?) Please answer !

BTW I need someone 3510i user's ICQ#, cause I have problems with my polyphonic reproductor and I want to ask you if it is anyone's problem or just mine... (I don't know if I should claim my phone or not). Please help me... My ICQ# is: 57173575, contact me.