Nevertheless, one of the hidden consequences of shifting development environment is the impact on the development team. "You can't just move a group of developers from J2EE to .Net; these are not complimentary skill sets," said Shreves. "You will lose people. You will lose good people."

He noted additional effort is also required to tap into the .Net community and pick up the required experience. That would require serious planning for the change as well as continuous screening and recruitment of team members.

Hong agreed that re-training Java programmers was a major initiative before the shift. Besides training Java programmers, various opportunities were also available in the past few years before Cascade replaced the PCS's development platform.

"Apart from the China Mobile project, last year when PCCW launched a series of new fixed-line residential services, many of the back-end support systems were developed by our team and they are .Net applications," he said.

By developing applications for other telcos using .Net, Hong said his team also built a stronger foundation before shifting the development environment of its core system. Meanwhile Cascade has also hired .Net developers to support the new platform.