OfBIz incorrectly initialised

(originally from JRA-4904)

We are experiencing similar problems. But they do only occur after a restart of Tomcat 5.0.19: Either Jira 2.6.1 works fine or it does not know its users or its navigator columns anymore (in which case we must restart Tomcat again and again until it works)...
These errors do not occur during normal operation, but only at startup time.
Note that the single, suddenly unknown field varies from restart to restart.
Examples:

...
Caused by: java.lang.IllegalArgumentException: [GenericEntity.set] "id" is not a field of SearchRequest
at org.ofbiz.core.entity.GenericEntity.set(GenericEntity.java:198)
at org.ofbiz.core.entity.GenericEntity.setFields(GenericEntity.java:524)
at org.ofbiz.core.entity.GenericEntity.<init>(GenericEntity.java:98)
at org.ofbiz.core.entity.GenericValue.<init>(GenericValue.java:63)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:765)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:744)
at com.atlassian.jira.issue.search.SearchRequestFactory.loadByMap(SearchRequestFactory.java:184)
at com.atlassian.jira.issue.search.SearchRequestFactory.getRequest(SearchRequestFactory.java:157)
at com.atlassian.jira.web.action.Dashboard.getSearchRequest(Dashboard.java:72)
... 85 more

...
Caused by: java.lang.IllegalArgumentException: [GenericEntity.get] "statusColor" is not a field of Priority
at org.ofbiz.core.entity.GenericEntity.get(GenericEntity.java:150)
at org.ofbiz.core.entity.GenericEntity.getString(GenericEntity.java:343)
at com.atlassian.jira.web.action.Dashboard.getPriorityStats(Dashboard.java:204)

...
java.lang.IllegalArgumentException: [GenericEntity.get] "passwordHash" is not a field of OSUser
at org.ofbiz.core.entity.GenericEntity.get(GenericEntity.java:150)
at org.ofbiz.core.entity.GenericEntity.getString(GenericEntity.java:343)
at com.opensymphony.user.provider.ofbiz.OFBizCredentialsProvider.authenticate(OFBizCredentialsProvider.java:54)
at com.opensymphony.user.User.authenticate(User.java:126)
at com.atlassian.seraph.auth.DefaultAuthenticator.login(DefaultAuthenticator.java:77)
at com.atlassian.seraph.auth.DefaultAuthenticator.getUser(DefaultAuthenticator.java:200)