This may be a Stata version problem as there was a time when string variables were constrained to be 80 or fewer characters long.  Using Stata 9.2, I was able to do the following:
. de
Contains data
  obs:            10                         
 vars:             1                         
 size:         1,040 (99.9% of memory free)
-------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-------------------------------------------------------------------------------
name            str100 %100s                 
-------------------------------------------------------------------------------
Sorted by: 
     Note:  dataset has changed since last saved
. recast str120 name
. de
Contains data
  obs:            10                         
 vars:             1                         
 size:         1,240 (99.9% of memory free)
-------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-------------------------------------------------------------------------------
name            str120 %120s                 
-------------------------------------------------------------------------------
Sorted by: 
     Note:  dataset has changed since last saved
>I have another simple question.  I've checked all that
>STATA manuals, and have read up on recast, but I am
>still having problems.  When I imported my data, STATA
>defaulted a string variable to str80 - so it cut off
>some of my responses.  I wanted to change the storage
>type to str200. I've used this command:
>
>. recast str100  q5mtype
>
>q5mtype:  str100 invalid
>r(109);
>
>
>While Stata will allow me to decrease the size (i.e. I
>could type: . recast str79 q5mtype, and it will accept
>me, but it will not allow me to increase the str size.
> Any ideas?
>
>Thanks,
>Buddy
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       Eric G. Wruck
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