How to update a customfield in Jira using jira4r

I am using jira4r to connect to Jira. So far I am able to create new RemoteIssues, update existing RemoteIssues (standard fields like summary), but I am not able to update a custom field.

I am able to create a new issue with values in the custom fields, and I am able t开发者_JS百科o read values from custom fields, but I have not been able to update a custom field.

Help appreciated.

a = Jira4R::V2::RemoteFieldValue.new
a.id = "customfield_10000"
a.values = 'blah'

b = Jira4R::V2::RemoteFieldValue.new
b.id = "customfield_10022"
b.values = 'test'

ticket = jira.getIssue('blah-105')
jira.updateIssue(ticket.key, [a, b])