It works smoothly and beautifully now (Thank you Stoneharry to bear with a newbie)
But just one problem , when i send the .mpq from the server(it contains the installer and the prepatch.lst)
The installer is extracted(i can see it in my folder) but it is not executed even if i log in using the wow client.
P.S. The Installer works nicely when it is run directly by putting it inside the folder and double clicking it.
And i have made prepatch.lst as per your instructions
sorry for troubling you so much
Edit:
It is done , i used a original mpq and replaced their installer with yours by renaming yours same as the original one
it works smooth and the whole patching process is complete but it shows an error at the end about not being able to rename the installed mpq as .trash but the game works well and no problem what so ever