I had created patches to add a few features to 1.6.2.X and 1.8.0, namely:
	comebackcontext
	comebackdialtime
	and a few other little tweaks

I have come to know that you can essentially do the same thing in the dialplan by doing the following:
(features.conf)
[general]
comebacktoorigin = no


(extensions.conf)
[general]
comebackdialtime=30
comebackdialargs=k


[company1-incoming]
; PCTCC stands for parked call timeout custom context.
; Use whatever you want.
exten => s,1,NoOp()
same => n,Set(__PCTCC=company1-pctcc)
same => n,Dial(SIP/222,,k)	; This extension will answer the call and park it


[parkedcallstimeout]
; Parked calls that timeout will come here if comebacktoorigin is set to no.
; The extension they come back to is the flattened version of their channel name,
; which means any forward slashes are replaced with underscores.
exten => _DAHDI.,1,Set(PTCHANNEL=DAHDI/${EXTEN:6})
same => n,Goto(s,1)

exten => _IAX2.,1,Set(PTCHANNEL=IAX2/${EXTEN:5})
same => n,Goto(s,1)

exten => _SIP.,1,Set(PTCHANNEL=SIP/${EXTEN:4})
same => n,Goto(s,1)

exten => _ZAP.,1,Set(PTCHANNEL=ZAP/${EXTEN:4})
same => n,Goto(s,1)

exten => s,1,GotoIf($["${DIALPLAN_EXISTS(${PCTCC},s,1)}" = "1" ]?${PCTCC},s,1)
same => n,Dial(${PTCHANNEL},,k)


[company1-pctcc]
exten => s,1,Dial(${PTCHANNEL},${comebackdialtime},${comebackdialargs})
same => n,Goto(company1-incoming,s,1)