Encypted mails in Blackberry

I had a casual doubt on mail encryption. One of my users sent an encrypted mail to some other users. One of the recipients is a Blackberry user. When he tried to open the mail, a message like" This email has been encrypted by Mr XXX" came and he’ unable to view the mail on his mobile. Can anyone suggest me a solution out? Thanks in advance

Subject: Encypted mails in Blackberry

I do know you have to have an up to date version of the blackberry server and I think that the notesID has to be stored in the mail file. This can be done by the user via a web browser using the iNotes/DWA interface.