When an image is bigger than the hypervisor free space you get a message like that:
SOURCE: Abiquo VDC_FERRAN_XEN / VAPP_FERRAN_XEN /
...
STACK TRACE: Its not possible to deploy the virtual application

SEVERITY: CRITICAL
...

You need to go to catalina.out to get the true message:
10:24:43.507 ERROR c.a.virtualfactory.rimpstub.RimpStub - Exception executing the RIMP WS-MAM operation com.abiquo.virtualfactory.rimp.RimpCreate
com.abiquo.virtualfactory.rimpstub.RimpException: There is no enough size to copy the file
/opt/vm_repository/1/rs.bcn.abiquo.com/ubuntu-server-karmic-x86_64/formats/177878e8-4448-4d0d-8d19-e801d8bbc8d2-VMDK_FLAT-ubuntu-server-karmic-amd64 to
/opt/localRepository/10.60.1.72__opt_vm_repository/

This message is more self explanatory.