While the mastery of a language - namely, the ability to use words properly - is crucial thinking and communicating clearly especially on highly specialised subjects, we merely need "pasar" knowledge of languages in order to be able to undertake commercial transactions.
I am constantly amazed to notice how easy people in the streets can speak a smattering of different languages and dialects and can be successful in making money. This you will notice in most urban centres where shopkeepers have to pay monthly rent and they are like rats constantly on the commerical treadmill. Necessity is the mother of invention, and the cost pressures simply force them to be innovative in their choice of location and store display and their ability to communicate to with all and sundry who pass by their store front. In Shanghai, the old ladies may even pull you into the shop by the arm.
The ability to speak in more than one language, I believe, comes from the desire to communicate with other people, to know who they are and what they are like. Without the desire for direct contact and communication, we tend to form judgement from hearsay and prejudices without proper verification. Communicating with other communities, even if only through books or the computer, is an effective way of doing away with ignorance and hence undue fear of what we do not know. The ability to hear what others say in their own languages give one a very clear picture of their what whole mental make-up. It fosters goodwill.
I, therefore, think that promoting a myriad of languages to be spoken and understood in Malaysia even if only among people mingling in the bazaars is an effort which the government, and not necessarily the education department, should undertake if it wants the country to globalise among ourselves and with others.