Change from GET to POST for form submission.

Add required hidden fields.
Change button name to "Action"

web/templates/msgs/msgs.inc

 <center>
 <P><A HREF="http://^^JS:system.inet_addr^^/">Home</A> :  <A href="/members/">Members</A> : <A HREF="index.ssjs">Groups</A> : <A HREF="subs.ssjs?msg_grp=^^group:number^^">%%group:description%%</A> : <B>%%sub:description%%</B>
 <A HREF="subinfo.ssjs?msg_grp=^^group:number^^&amp;msg_sub=^^sub:code^^">[?]</A> -> <a href="post.ssjs?msg_grp=^^group:number^^&amp;msg_sub=^^sub:code^^&amp;post=new">Post New Message</a></P>
-<FORM action="management.ssjs" METHOD="GET">
+<FORM action="management.ssjs" METHOD="POST">
+<INPUT TYPE="hidden" NAME="msg_grp" VALUE="^^group:number^^">
+<INPUT TYPE="hidden" NAME="msg_sub" VALUE="^^sub:code^^">
 <TABLE class="msglist" cellpadding=5 CELLSPACING=0 BORDER=1 WIDTH="100%">
 <TR class="msglist"><TH class="msglist"><font color=black>X</FONT></TH><TH class="msglist"><font color=black>A</font></TH><TH class="msglist"><font color=black>Subject</font></TH><TH class="msglist"><font color=black>From</font></TH><TH class="msglist"><font color=black>To</font></TH><TH class="msglist"><font color=black>Date</font></TH></TR>
 <!-- %%JS:template.color=0%% -->
@@ -29,7 +31,7 @@
 <<END REPEAT messages>>
 </TABLE>
 <br>
-<INPUT TYPE="Submit" NAME="Delete" VALUE="Delete Message(s)">
+<INPUT TYPE="Submit" NAME="Action" VALUE="Delete Message(s)">
 </FORM>
 @@pagelinks@@
 </center>