"waterworks" = one who cries excessively

[Benjamin Zimmer]

Here's an odd transferred sense of "waterworks" I hadn't seen before...

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http://www.salon.com/ent/col/fix/2005/11/07/mon/index.html
She [Jennifer Aniston] also takes time to point out she's not the
waterworks she has been made out to be since her marriage went sour. "I'm
pegged as a crier, aren't I? I was upset about the Vanity Fair article. I
had one moment when I got emotional because I hadn't sat down with an
interviewer since this whole debacle took place. It happened for a second
and then it was over."
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I thought it might be a nonce form, but I managed to find some similar
examples:

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You have been quite the waterworks the past week and last night at
gradgeation.
http://www.trackforums.com/forum/archive/index.php?t-648.html
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Sometimes, If a guy is being a real waterworks, it's a turn-off.
http://www.musicianforums.com/forums/showthread.php?t=331531&page=3
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In my old age I'm turning into a real waterworks - the tears first
appeared as they were flying kites, and it was all downhill from there.
http://scroobious.blogspot.com/2005/04/london-full-of-everywhere-else.html
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[at Carrie's very emotional and weepy goodbye dinner - Charlotte in
particular is being a total weepy waterworks]
http://www.imdb.com/title/tt0159206/quotes
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I was a total waterworks because my neighbor and him were friends and
students together and when he was playing.
http://www.woohu.com/postcomment.php?id=485002
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I've been a total waterworks lately.
http://www.inthemix.com.au/forum/showthread.php?t=132913&page=2
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Okay, i know that i'ma waterworks but did anyone else cry when Cher died
on wolf's rain?
http://www.animerise.com/index.php?act=Print&client=printer&f=5&t=9423
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I get that from my Mom; she's a waterworks.
http://www.reinyday.com/rachel/daily/diary002.html
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I suppose if a modifier like "total" or "real" precedes "waterworks" it
sounds a bit better, but it still seems strange. I'm not sure what
agentive form I'd prefer ("waterworks factory"? "waterworker"?). For me,
"waterworks" is too idiomatic (only appearing in set expressions like
"here comes the..." or "turn on the...") to take on any extended meanings.


--Ben Zimmer