The Host Integration Server Product Team has just released the fifth Cumulative Update (CU) for HIS 2010. The cumulative update model is used to package and release product fixes on a more consistent schedule.
HIS 2010 CU5 includes fixes for HIS 2010 that were fixed after the release of HIS 2010, including all the fixes that are in the previous HIS 2010 cumulative updates. Details on the included fixes can be found in the following Knowledge Base article:
2728515 Cumulative update package 5 for Host Integration Server 2010 http://support.microsoft.com/kb/2728515/EN-US
You can download HIS 2010 CU5 via the Hotfix Download Available link in the KB article. You would need to download the CU5 package that matches the HIS 2010 version (x86 or x64) that you have installed.