RFC which the stack is in compliance with

2976 - INFO
no

3204 - ISUP & QSIG MIME 
no 

3261 - sip 
all including S/MIME and TLS 

3262 - Reliabilae provisional responses
Not suported

3263 - SIP Locationt
- partial support only 
- currently SRV and NAPTER are not supported

3264 - Offer/Answer
Yes

3265 - Events
Yes

3310 - AKA
Not sure - probably 

3311 - Update 
no 

3312 - Preconditions
Maybey - not sure

3420 - sipfrag
yes

3323 - Privacy 
no

3325 - Asserted-Identity
no

3428 - MESSAGE
yes

3326 - Reason
no

3327 - Path
no

3329 - Sec Agree 
yes

draft-ietf-impp-cpim-pidf-07.txt
yes

http://www.ietf.org/internet-drafts/draft-ietf-sip-callerprefs-07.txt
hmm

draft-message-waiting
yes

2311 - S/MIME ver 2 spec 
yes

2045 - MIME part one
yes

2046 - Mime part two
yes

2633 - S/MIME ver 3
yes

2315 - PKCS#7 
yes

1847 - Secure Multipart MIME 
yes