Undefined function or variable, matlab classes

Hello, when I add methods to my Matlab class, Matlab got always problems to recognize them and I usually get the error:

Undefined function or variable 'abc'.

No the methods are in scope and I got no problems with naming them right or something, it is just about the recognition of matlab. After some time Matlab starts to recognize them and when I don't change the recognized functions it stays like that. Actually even rehash, clear functions, clear mex does not help.

What can I do to overcome this problem?

Thank you in advance.

[Sean de Wolski]

Can you post an example class that shows this error?

[John D'Errico]

I always do a

clear classes

to force things to be recognized.

[baxbear]

Thank you very much, clear classes seems to work for me too, couldn't find this.