Looks like you system might be leeking call-legs, or all have been consumed and non are available for new calls. There might be some additional issue unknown occurring on your system right now leading to this behavior (for instance mis handled sip messages). Really the only way to handle this going forward due to its complexity, is to reported the issue to technical support team at Dialogic. However that would require that you have a Service Level agreement (tied to the HMP license on the server) with them in order to have the issue reviewed. Here is a link to more information on that:
www.dialogic.com/.../HMP-SR140-enterprise-software-services.htm
Ideally, debugging this type of issue via forum at this point get a bit too involved since a lot of lower level logging and analysis would need to be done at this point (back and forth). And that is not the point of the "developers forum" to debug run time live site issues.
Regards,
Jeff