In OAS (10.1.2.0.2), webforms, when using a left-handed mouse to expand a menu, the tree node is not expanding. No error is given.
For example, in ‘Material Workbench’ select the ‘+’ to expand ‘Organizations’ in the menu.
Left and right button does not do anything.
Also, the left handed users are having difficulties in moving screens with the mouse.

Oracle states that this is a bug (note 196844.1, bug 2200274), in Jinitiator (we are using 1.3.1.22)
Just to be sure, I installed Jinitator 1.3.1.30:  same behaviour.

Solutions
1 Install  Sun Java (5.0.6)  instead of  Jinitiator. This definitely works. Wrote another post on this matter to use Sun instead of Jinitiator.
2 Update of the (Microsoft Intellipoint) mouse-driver. Did not work for us. Problems with the mouse-driver in our environment
3 Oracle work-around in the note: use a right-handed mouse… => no comment.
4 Use the keyboard for that part of the functionality. We got unexpected results from this. At first it seems to be working, but the results didn’t match the results when we use the (right-handed) mouse. Also you have to program the ‘focus’ of the mouse or cursor in that case.

As there is no support for Jinitiator anymore, and the Intellipoint didn’t do what we expected, we’ve chosen for nr 1.

Sources:

Note: 274100.1 – Left Hand Mouse Does Not Expand Tree Node In Oracle Forms

Note: 760250.1Diagnosing Forms Mouse Focus Problems Using JRE in Release 11i

Note: 290807.1 - Deploying Sun JRE (Native Plug-in) for Windows Clients in Oracle E-Business Suite 11i