Re-INVITE transactions takes too long to be cleared when failed final response is received, causing application to unable to send subsequent re-INVITE (thanks Ruud Klaver for the report)

[bennylp]

The invite session maintains the current/active INVITE transaction, since there can only be one invite transaction active. This variable is not cleared when the re-INVITE is answered with final response, it's only cleared after the INVITE transaction is terminated (in 32 seconds or so), causing application to unable to send subsequent re-INVITE in this period.