Uncaught Exception on package:(de)activate when package is already (de)activated or not specified.
Try to activate a package that is already active, like TYPO3.FLOW3 or TYPO3.Fluid
./flow3 package:activate TYPO3.FLOW3
FLOW3 should say something like "Package is already active", but instead it throws an "Uncaught Exeption" with pretty useless information:
Uncaught Exception More Information Exception code #0 File [snip]Cache/Code/FLOW3_Objet_Classes/TYPO3_FLOW3_Cli_CommandController_Original.php line 249 Exception reference #201204413235602f31b8f
The same exception occurs if you deactivate an already deactivated package.
If you don't specify the package to activate with
./flow3 package:activate, you get the same fairly useless error message (only it cites line 172 instead of 249).