We have been running Bamboo version 4.2.1 for a while on JDK 1.6 without problems. For what it's worth the installation was upgraded to 4.2.1 from 4.1 a few weeks ago.
There is now a requirement to run the Sauce Labs Bamboo Sauce OnDemand plugin (https://marketplace.atlassian.com/plugins/com.saucelabs.bamboo.bamboo-sauceondemand-plugin) in order to complete our test execution. The developer suggests the plugin requires JDK 1.7 to operate correctly.
We verified that Bamboo 4.2.1 does support JDK 1.7, shutdown Bamboo, switched to JDK 1.7 and encountered problems starting up. Bamboo throws errors in the logs and HTTP requests respond with a 503 Error, noted below. Once we switched back to JDK 1.6, Bamboo started again successfully. Logs for Bamboo startup using JDK 1.6 and JDK 1.7 are attached.
HTTP ERROR: 503
Problem accessing /. Reason:
Service Unavailable