how to create duplicate aapln/how to change exising appln name

hi i have created one webdynproproject

i want to keep existing prj as it is

1)i have changed existing project name and imported that

since appln name is same i am getting deployment error

2)i have created new appln and used exising component then also deployment error

can anybdy suggest me how to have 2 copies of same project in webdynpro explorer