No he is completely right. WiMAX does not desginate 4G status, WiMAX is merely a wireless transmission medium. On the other hand XOHM is 4G WiMAX. http://en.wikipedia.org/wiki/Xohm
Many companies have taken self-serving definitions and distortions about 4G to suggest they have 4G already in existence today, such as several early trials and launches of WiMAX, which is part of the formal ITU standard for 3G.
There is no formal definition for what 4G is; however, there are certain objectives that are projected for 4G. These objectives include: that 4G will be a fully IP-based integrated system. 4G will be capable of providing between 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security. [1]