According to Jaspersoft's documentation, though it may technically be possible based on the technology being used to connect to LDAP (Spring Source), it's not certified or tested by Jaspersoft. Their recommendation is as follows:
" Our engineering department recommends solving the problem on the LDAP level. The LDAP provider should have fully certified features to support the various scenarios as mentioned above or more, Jasper Server would simply connect as usual to the top controlling LDAP server."
Based on this information CABI JasperReports Server 6.2 is not certified for use with multiple LDAP environments.