Transaction Iview question

Hi experts, Gurus and others

I have a transaction iview that gives the portal users via ITS the transaction SSC1. Now everything works, but in the menu Goto->open other calendar. The "open other Calendar" is grayed out (disabled). In the CRM system it is not.

Now I think that is because the shortcut in the CRM system for that function is F5, and for Internet Explorer F5 is for refreshing.

Anyone has a solution to this problem or has an other explanation?

thanks in advance