PKZIP Encryption Been Compromised?

["Reply to: hahn@lds.loral.com" <HAHN@lds.loral.com>]

A friend of mine tells me that the encryption feature of the PKZIP
compressor/archiver is vulnerable.  I have been using it for
private material that is not to be passed to anybody else.
To what extent is this material vulnerable to attack, given
that the attacker has no examples of a plaintext/ciphertext pair
using my key.  Also, to what extent is the vulnerability a function
of the key length?

Thanks in advance to anybody who can help me.

Karl

|         (V)              |  "Tiger gotta hunt.  Bird gotta fly.
|   (^    (`>              |   Man gotta sit and wonder why, why, why.
|  ((\\__/ )               |   Tiger gotta sleep.  Bird gotta land.
|  (\\<   )   der Nethahn  |   Man gotta tell himself he understand."
|    \<  )                 |  
|     ( /                  |                Kurt Vonnegut Jr.
|      |                   |  
|      ^                   |