Blackberry not working

i have migrated some users to exchange 2003 to Exchange 2007 , they use blackberry srevice … while configuring Blackberry Devise it with Exchange 2003 Users it working fine without any issues,and the same thing New created in Exchange 2007 users it working fine but if i migrate the user from exchange 2003 to exchange 2007,accept Blackberry is it not wroking others things are wroking fine can you help me in this.