Invalid username or password

Posted this in the Openfire section but it may simply be a Spark problem?

I’m testing out Openfire/ Spark and was getting on ok until this, I have one test user who has a pound symbol £ in the password. Any time I try to log on with this account I get an invalid username or password error!

I tried setting up another user with the same password and I get the same error! I’m pulling users from Active Directory so I can’t ask people to change their confidential passwords if they have a £ symbol in them as that would affect the whole company.

Can anyone confirm or deny that the problem is indeed the £ symbol? and more importantly can anyone suggest a fix? Are there any other unsupported symbols?

TIA for any help