It appears that a few clients have problems using ssh1 to authenticate to servers with pam-ldap setup.

• Eclispe Bug report

Here are some links:

• The eclipse extssh connection protocol uses a java based ssh1 client. Here is a report of it having problems: http://blogs.cocoondev.org/crafterm/archives/001940.html
  The developers at CC have had this same problem using extssh.
• Here is a report of putty having a similar problem: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=104576