[PD] [command] can't execute "ls | wc -l"

[Alexandros]

While [ggee/shell] outputs the correct number of files in a directory 
with the message "ls | wc -l", [command] outputs an error code 2 with 
"exec ls | wc -l" and doesn't output anything.

Is this intentional? If so, how can this command be executed by [command]?