strange problem

dear friends

I am configuring KM and Collaborations

I have strange problem in Versioning.

I enabled Versioning in a Public Document folder, and uploaded a file.

If i upload the same file again on the same folder, instead of creating new versioned file, it is uploading again.

If i want to keep versioned file, i have to upload the file from the file properties.

I want the version file should create even i upload from the folder itself.

Please help me anybody.

thanx in advance

kantha