When I want to print the date and time of the last modificatión of a file, while the weekday and month of teh date appears in english, the timezone appears in the language locale of the computer (in my case, spanish). 

Both should be in the same language, and, preferibly, the output language of the date format should be configurable,

While some unix/linux versions read a LANG enviroment variable and use it correctly, in Windows it uses inconsistently the system locale.