Exporting table through call method

Hello experts,

I'm trying to make my get_entity_set methode for a condition type:

DATA itab_cond_type TYPE TABLE OF zstruc_cond_type.

DATA wa_cond_type type zstruc_cond_type.

     CALL METHOD class->GET_COND_TYPE IMPORTING ex_cond_type  = itab_cond_type

         .

   DATA: ls_entityset LIKE LINE OF et_entityset.

LOOP AT itab_cond_type INTO wa_cond_type.

     ls_entityset-KSCHL = wa_cond_type-KSCHL.

     ls_entityset-class = wa_cond_type-VTEXT.

     APPEND ls_entityset TO et_entityset.

ENDLOOP.

I get an error at the import.   => "itab_cond_type" is not type-compatible with the

formal parameterr "ex_cond_type".

Even though they are both from the same type ... (type table of zstruc_cond_type).

When i change 'DATA itab_cond_type TYPE TABLE OF zstruc_cond_type' to 'DATA itab_cond_type TYPE zstruc_cond_type'

i get an error at the loop at because it is no longer an iternal table and i cannot append my data to et_entityset...

Any ideas of what it is i'm doing wrong here?

Kind regards,

Bart