The problem is that ActivePerl uses the crypt_r() function which needs a buffer to work with, and that argument requires one of its fields to be nulled. ActivePerl allocates this buffer on the stack, so the said field may be non-null.

The following patch has been checked in:

--- ./pp.c.~1~      Tue Sep 17 14:17:07 2002
+++ ./pp.c  Tue Sep 17 14:17:07 2002
@@ -2347,6 +2347,7 @@
 #  if defined(__linux__)
 #   include <crypt.h>
     struct crypt_data c_data;
+    c_data.initialized = 0;
 #    define crypt(k,s) crypt_r(k,s,&c_data)
 #  endif
 #endif
End of Patch.
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There should be a new release out for Linux ASAP.