[WINTCL] can't find package httpd::threadmgr 1.0

[Abhishek T. <abh...@au...>]

if { [lsearch $auto_path [file dirname [info script]]] == -1 } {
    lappend auto_path [file dirname [info script]]
}

lappend auto_path  "C:/LM_120_with_unittests/dist/tclweb/lib"

package require Tcl 8.3
package require base64 2.2

if { ![info exists tclModeEmbedded] } {
    package require httpd::threadmgr 1.0
#package require httpd::threadmgr
}

My code is above and its failing and giving error :
can't find package httpd::threadmgr 1.0

package require Tcl 8.3 - What does this statement mean. is this the
reason. I changed it to 8.5 or 8.4, did not work. I  dont think I have 8.3
on my machine.

Please help

Regards
Abhishek