Aaron-Staples-MacBook-Pro:mongo8 aaron$ ./mongo jstests/currentop.js && echo success
MongoDB shell version: 2.3.0-pre-
connecting to: test
BEGIN currentop.js
count:100
start shell
Thu Sep 13 20:25:57 shell: started program /Users/aaron/src/mongo8/mongo --eval db.jstests_currentop.count( { '$where': function() { sleep(1000); } } ) 127.0.0.1/admin
sleep
sh15244| MongoDB shell version: 2.3.0-pre-
sh15244| connecting to: 127.0.0.1/admin
sh15244| 0
inprog:
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inprog:
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wait have some ops
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...

assert.soon failed: function () {
    return ops({'locks.^test':"r", ns:"test.jstests_currentop"}).length + ops({'locks.^test':"R", ns:"test.jstests_currentop"}).length >= 1;
}, msg:have_some_ops
Error("Printing Stack Trace")@:0
()@src/mongo/shell/utils.js:37
("assert.soon failed: function () {\n    return ops({'locks.^test':\"r\", ns:\"test.jstests_currentop\"}).length + ops({'locks.^test':\"R\", ns:\"test.jstests_currentop\"}).length >= 1;\n}, msg:have_some_ops")@src/mongo/shell/utils.js:58
((function () {return ops({'locks.^test':"r", ns:"test.jstests_currentop"}).length + ops({'locks.^test':"R", ns:"test.jstests_currentop"}).length >= 1;}),"have_some_ops")@src/mongo/shell/utils.js:167
@jstests/currentop.js:41

Thu Sep 13 20:26:28 uncaught exception: assert.soon failed: function () {
    return ops({'locks.^test':"r", ns:"test.jstests_currentop"}).length + ops({'locks.^test':"R", ns:"test.jstests_currentop"}).length >= 1;
}, msg:have_some_ops
failed to load: jstests/currentop.js

diff --git a/src/mongo/shell/servers_misc.js b/src/mongo/shell/servers_misc.js
index 99a94b9..0d094b4 100644
--- a/src/mongo/shell/servers_misc.js
+++ b/src/mongo/shell/servers_misc.js
@@ -269,7 +269,7 @@ function startParallelShell( jsCode, port ){
 
     if (typeof db == "object") {
         // Must start connected to admin DB so auth works when running tests with auth.
-        args.push(db.getMongo().host + "/admin");
+        args.push(db.getMongo().host);
     }
 
     x = startMongoProgramNoConnect.apply(null, args);