The agent in the following IBM technote will resolve this issue. I have also used this agent with the 8.0.x and 8.5.x versions as well as the versions listed in the technote….
<a href=”http://www-01.ibm.com/support/docview.wss?fdoc=wplcnote&rs=475&uid=swg21164501″>’Your availability time range is invalid’</a>
Appearantly, Lotus Notes is looking for a 24 hour time format, even though as soon as you click away from the entry it returns it to a 12 hour format display. I was able to fix the issue by entering in my availability using a 24 hour time and the associated AM/PM needed. Odd, but it worked.