JavaCard OS

I used JCIDE to debug my applet.

Then I sent the following commands consecutively.
>/select 112233445501
>90 00
/send 00a4000002f801
>6F FF
/send 01a4000002f801 ?? 6A 95 expected
>68 81
/send 08a4000002f801
>6A 95

Q: The third and the fourth commands should output 6A 95. But the third output 68 81.
What was going on ? Why 6A 95 didn't occur?
Thanks.

The two least significant bits of the CLA byte encodes the logical channels numbers. If you set CLA to 07, it won't find any open channel except the basic one(0). So the platform handles the error before the applet receives your APDU command.
That is your applet doesn't receive the command at all.