Unable to delete file with netbeans 6.1 and jdk1.5

Hi,

I am using Netbeans 6.1 with jdk1.5.0_15. While Clean & Build a project I am getting the following error. I have seen different post regarding that issue in different forums and I come to know that in Netbeans 6.1 this bug has been resolved, but I am still facing it and believing that I cannot able to use netbeans. Is there anyone who know any workaround to solve this problem?
Here is the output of my build:

pre-init:
pre-load-properties:
exists.config.active:
exists.netbeans.user:
exists.user.properties.file:
load-properties:
exists.platform.active:
exists.platform.configuration:
exists.platform.profile:
basic-init:
cldc-pre-init:
cldc-init:
cdc-init:
ricoh-pre-init:
ricoh-init:
semc-pre-init:
semc-init:
savaje-pre-init:
savaje-init:
nokiaS80-pre-init:
nokiaS80-init:
nsicom-pre-init:
nsicom-init:
post-init:
init:
conditional-clean-init:
conditional-clean:
pre-clean:
clean-timestamp:
Deleting: C:\java\Projects\MAS\build\.timestamp
clean-preprocessed:
Deleting directory C:\java\Projects\MAS\build\preprocessed
clean-classes:
Deleting directory C:\java\Projects\MAS\build\compiled
clean-obfuscated:
clean-preverified:
clean-manifest:
clean-jar:
Deleting: C:\java\Projects\MAS\dist\MAS.jar
C:\java\Projects\MAS\nbproject\build-impl.xml:327: The following error occurred while executing this line:
C:\java\Projects\MAS\nbproject\build-impl.xml:1050: Unable to delete file C:\java\Projects\MAS\dist\MAS.jar
BUILD FAILED (total time: 0 seconds)

Regards,
Farooq