The workaround is to do it using the CLI command :
provision-ap copy-provisioning-params ap-name 00:00:00:00:00:00
provision-ap installation default
provision-ap ipaddr 1.1.1.1.
provision-ap netmask 255.255.255.0
provision-ap gateway 1.1.1.254
provision-ap dns-server-ip 1.1.1.253
provision-ap domain-name domain.net
provision-ap no external-antenna
provision-ap server-name aruba-master
provision-ap ap-group "Group1"
provision-ap ap-name "AP1"
provision-ap no syslocation
provision-ap mesh-role none
provision-ap no fqln
provision-ap reprovision ap-name 00:00:00:00:00:00
But you should consider upgrading to a later code that has a fix for that.