I'm no expert but it sounds like too much water to me.

MD

From: (Andrew_Rodriguez)
Organization: http://groups.google.com/
Newsgroups: rec.gardens.orchids
Date: 10 May 2003 16:12:55 -0700
Subject: Beginner needs help!

Greetings,

Several weeks ago, I purchased my first orchid - from the phalaenopsis
family. I carefully repotted the plant and for two weeks it was doing
fine. However, in the past few days one of the leaves became limp and
soft.

Any one have any idea on what's happening? I've been doing my best to
'do it by the book'. However, I'm not sure what this is a symptom
for...

Thanks in advance,
Andrew