Index: src/java/org/apache/poi/ss/usermodel/DataFormatter.java
===================================================================
--- src/java/org/apache/poi/ss/usermodel/DataFormatter.java	(revision 1096425)
+++ src/java/org/apache/poi/ss/usermodel/DataFormatter.java	(working copy)
@@ -351,6 +351,7 @@
         formatStr = formatStr.replaceAll("\\\\/","/"); // weird: m\\/d\\/yyyy 
         formatStr = formatStr.replaceAll(";@", "");
         formatStr = formatStr.replaceAll("\"/\"", "/"); // "/" is escaped for no reason in: mm"/"dd"/"yyyy
+        formatStr = formatStr.replaceAll("\\\\.", ".");
 
         boolean hasAmPm = false;
         Matcher amPmMatcher = amPmPattern.matcher(formatStr);