[Serusers] Checking Authorization Username == From: Username

I have a requirement to ensure that Authorization Username == From: Username before a call is allowed. I would appreciate any advice, guidance or reference to other resources that may enable me to do this. Kind regards, Russell Bate Livewire International -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.362 / Virus Database: 267.12.6/152 - Release Date: 31/10/2005 The information transmitted including any attachments is intended only for the exclusive use of the person(s) or entity to which it is addressed and may contain confidential and privileged material that may be subject to legal privilege. Any perusal, review, retransmission, dissemination, distribution, reproduction or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient without the sender's prior consent is unauthorised and strictly prohibited. If you have received this message in error, please notify the sender immediately and delete the message from your computer.