Strange behaviour if zsh starts with a TERM that is unknown

["C. v. Stuckrad" <stucki@math.fu-berlin.de>]

Hi!

By 'messing up' my zsh-setup I found a strangely different behaviour
of the following two cases:
1) Normal setup TERM=something_existing
      zsh starts and ZLE works, 
   NOW I SET TERM to something unknown,
      (I get an errormessage)
      Single-Line-ZLE works

2) STARTUP of a zsh with UNKNOWN TERM 
      *** NO ZLE WORKS (correctly) ***
      - delete (backspace) echo 'BLANKs' and move RIGHT !
      - ^U echos as many blanks as there wee typed chars
      - ^L rewrites the 'Line', but without Newline/Carriage-Return

It seems not to depend on the Version, as far back as 2.6.

Clueless,   Stucki

PS.: Does somebody have a 'program' or 'script' which tests the existence
     of the 'current'(or a given) Terminal-Description. 

Christoph von Stuckrad       * *  | talk to  | <stucki@math.fu-berlin.de> \
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