Pass Jira issue.key to Bamboo via webhook

[David Meadow]

I am using the webhook:

http://yourusername:yourpasswd@bamboo-host:8085/rest/api/latest/queue/PLAN-KEY?os_authType=basic 

in Jira to trigger a Bamboo build on issue creation. The trigger works and the plan runs. All good except I have no way to update Jira as there is no issue key to use. How can I pass that value? Webhooks have the ${issue.key} variable available, but the best I have achieved is to have the trigger work and Bamboo ignore the variable. There has to be a way to do this right?