Error comes in building the boost-linux.yml build

[satyamakgec]

After executing this command -- sudo ./bin/gbuild ../batan/contrib/gitian-descriptors/boost-linux.yml
following things happen --
[sudo] password for explorer:
--- Building for precise i386 ---
Stopping target if it is up
Making a new image copy
Formatting 'target-precise-i386.qcow2', fmt=qcow2 size=11811160064 backing_file='base-precise-i386.qcow2' encryption=off cluster_size=65536 lazy_refcounts=off
Starting target
Checking if target is up
Preparing build environment
sending incremental file list
boost_1_55_0.tar.bz2
58,146,647 100% 10.84MB/s 0:00:05 (xfr#1, to-chk=0/1)

sent 58,160,973 bytes received 34 bytes 6,842,471.41 bytes/sec
total size is 58,146,647 speedup is 1.00
Updating apt-get repository (log in var/install.log)
Installing additional packages (log in var/install.log)
Creating package manifest
E: I wasn't able to locate a file for the cron package. This might mean you need to manually fix this package.
E: Unable to correct problems, you have held broken packages.
./bin/gbuild:21:in system!': failed to run on-target -u root bash < target-bin/grab-packages.sh > var/base-precise-i386.manifest (RuntimeError) from ./bin/gbuild:108:in build_one_configuration'
from ./bin/gbuild:285:in block (2 levels) in <main>' from ./bin/gbuild:280:in each'
from ./bin/gbuild:280:in block in <main>' from ./bin/gbuild:278:in each'
from ./bin/gbuild:278:in `

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how do i resolve this issue