shell script to cap first letter?

[Gary Kline]

guys,

i'm wondering if there is a script that i could run my plaintext
files thru that would capitalize thef first letter of each
sentence [[ assuming the character wasn't already a cap!]]

more and more, in recent years, i have posted questions or
written things that have been sloppily or casually hacked
together in all lower case.  this filter would have to determine
what was and was not a sentence.  or a sentence fragment.  
[ai]spell can catch "i've" and suggest "I've", etc.  

ideas?

-- 
 Gary Kline  kline at thought.org  http://www.thought.org  Public Service Unix
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