I can see that the pull request https://github.com/civicrm/civicrm-core/pull/4708/files which Jitendra claimed fixed the issue is not in version 4.7.1. It seems that it may have caused an issue and was therefore backed out - but I have not sleuthed that far so I am only surmising.
It‘s a fairly straightforward fix - but I do not feel I understand the potential knock ons particularly if it did introduce this other bug or not.
Your options are:
1) Go ahead and apply that one line fix manually or have your sysadmin do it, and back up everything and test thoroughly.
2) Report it as a bug and wait for it to be addressed.
3) Report it as a bug and provide funds for a core team member to examine it sooner. Show the previous ticket and let them sleuth it out. As there is a fix already there it probably will not take long to confirm if it did cause the other issue, and if so prevent that.
4) Recruit your local CiviCRM partner agency to examine this for you and make the best decision for you and your client.