Assist with configuring call park in FreeSwitch 1.4

Looking for a FreeSwitch Expert to provide configuration expertise with call park configuration. Responsibilities: Assist with configuring call park in freeswitch 1.4 Scenario Background: Participants UA1, UA2, callpark ext (FS) 1. UA1 calls UA2, call established 2. UA2 parking a call (making transfer to call park ext) 3. UA1 hears MOH. 4. UA2 unpark a call (call to *78 + callpark ext) 5. call in progress again 6. UA2 parking a call again (making transfer to call park ext) 7. UA1 hears MOH. 8. UA2 unpark a call (call to *78 + callpark ext) What is currently not working for us: I. On step 2. During transfer, UA1 got REFER message, which contains PARKEXT as callee so UA1 display that value on screen ("to: PARKEXT"). At this point we believe we have a misbehavior, because for UA1 it should look like UA2 put call on hold, so no PARKEXT should be shown on UA1 display. II. On step 4. UA2 wants to unpark a call, and making a call to *4PARKEXT (or *78PARKEXT). This can be done by pressing blinking lamp on parking extension BLF button. But in both cases, we making a call, and Freeswitch handle it. So at this point FS control what UA1 and UA2 can see as caller and calllee ID. In our tests on UA2 we see *78PARKEXT as remote party, and on UA1 PARKEXT as remote party. But at this point we should have UA1 as remote party for UA2 and vise versa. This broken point affects the rest of the scenario and definitely this should be fixed. III. After unpark, If UA2 going to park call again, it make transfer to PARKEXT, but because of II. in REFER to UA1 (same as in step 2.) request URI and To field contains UNPARKEXT, but not PARKEXT. What is needed: a) On step 2, after FS answers a call, it sent REFER to UA1. REFER contains park ext as callee. It breaks UA1 caller display id and SSS constructs invalid notification for BLF. We need to fix FS-side SIP signalling in a following way: for UA1 it should look like UA2 just put call on hold, + call-park extension should appear in remote-party-id field. b) On step 4, when FS bridges parked call back, we should again see UA2 as callee in SIP, call-park extension should appear in remote-party-id field. Our expectation is the following: For UA1 call will look like call with UA2 only. For our BLF monitoring of the Park extension we will use remote-party-id field to construct proper notifications.