I was using grails in version 2.2.0 on Ubuntu for some time and everything went good. My application ran fine. I updated my JDK to 1.7.0_25
If upgrading is an issue I posted a comment on the grails bug for a (non destructive) workaround which at least in my case works with 2.2.1:
http://jira.grails.org/browse/GRAILS-10183?focusedCommentId=76068&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-76068
Edit grailsw
#### start of hack to workaround GRAILS-10183 (http://jira.grails.org/browse/GRAILS-10183)
SPRINGLOADED_CORE_1_1_3="../../local-maven-repo/org/springsource/springloaded/springloaded-core/1.1.3/springloaded-core-1.1.3.jar"
STARTER_CLASSPATH="$SPRINGLOADED_CORE_1_1_3:wrapper/grails-wrapper-runtime-2.2.1.jar:wrapper:."
#STARTER_CLASSPATH="wrapper/grails-wrapper-runtime-2.2.1.jar:wrapper:."
#### end of hack to workaround GRAILS-10183 (http://jira.grails.org/browse/GRAILS-10183)
Now when you use the grails wrapper springloaded core 1.1.3 is first in the classpath and it just works. Since both the jar file and grailsw are checked in with the source tree, anybody who checks it out benefits from the fix which is better than asking everybody to hack their local grails install.