Situation:
We write a SOAP client for JIRA in JAVA. The client creates issues in JIRA and keeps issue's key.
If you login directly to JIRA and move the issue to another project in JIRA (issue's key changes), a call of
com.atlassian.jira.JiraSoapService.getIssue(jiraSessionToken, issuekey)
using the original key fails.

On the other hand:
Searching for an issue in JIRA via 'QUICK SEARCH' (even searching for a moved issue using its 'old' issue key) works fine and shows the (moved) issue.

Whish:
A call of
com.atlassian.jira.JiraSoapService.getIssue(jiraSessionToken, issuekey)
should find the issue even if the issue was moved i.e. 'issuekey' is an 'old' one.