ContentLength SIPHeader (of which there can be only one in a SIPMessage).
Fielding, et al. Standards Track [Page 119] RFC 2616 HTTP/1.1 June 1999 14.13 Content-Length The Content-Length entity-header field indicates the size of the entity-body, in decimal number of OCTETs, sent to the recipient or, in the case of the HEAD method, the size of the entity-body that would have been sent had the request been a GET. Content-Length = "Content-Length" ":" 1*DIGIT An example is Content-Length: 3495 Applications SHOULD use this field to indicate the transfer-length of the message-body, unless this is prohibited by the rules in section 4.4. Any Content-Length greater than or equal to zero is a valid value. Section 4.4 describes how to determine the length of a message-body if a Content-Length is not given. Note that the meaning of this field is significantly different from the corresponding definition in MIME, where it is an optional field used within the "message/external-body" content-type. In HTTP, it SHOULD be sent whenever the message's length can be determined prior to being transferred, unless this is prohibited by the rules in section 4.4.
@author M. Ranganathan
@author Olivier Deruelle
@version 1.2 $Revision: 1.7 $ $Date: 2009-10-18 13:46:34 $
@since 1.1