Problem with inputParser and anonymous functions for validators

[Jose]

Hello.

I am trying to use inputParser and anonymous functions for validators. I 
get errors, as follows.

octave:2> p = inputParser;
octave:3> val = @(x) ischar(x);
octave:4> val('hello')
ans =  1
octave:5> p = addRequired (p,"pack", @val);
error: @val: no function and no method found
error: evaluating argument list element number 3
octave:5> p = addRequired (p,"pack", @ischar);


Any hints?
I am using octave 3.6.2 and general package 1.3.2

BR
Jose