4. A wireless communication device comprising: a processor; machine readable memory in communication with said processor, storing machine-executable virtual machine software controlling operation of said device, said virtual machine software comprising: a parser for receiving a markup language document comprising a single markup language element defining a mathematical operation to be performed upon specified numerical operands; a screen generation engine, for presenting at least one user interface screen at said device in accordance with said markup language document; at least one event handling routine for processing events arising in response either to interaction with said at least one user interface screen or to a message received over a wireless network in accordance with said text file; and at least one object-oriented class corresponding to an action to be performed by said device in response either to said interaction with said at least one screen or to said message received over said wireless network, said action comprising performing said mathematical operation upon said specified numerical operands, wherein said numerical operands are floating point operands and wherein said single markup language element comprises an attribute indicating a desired number of decimal places to be displayed to the right of a decimal point of a floating point result of said mathematical operation, and wherein said performing said mathematical operation comprises rounding a least significant digit of said floating point result that is to be displayed in accordance with said desired number of decimal places based on a value of a most significant digit of said floating point result that is not to be displayed in accordance with said desired number of decimal places.
4. A wireless communication device comprising: a processor; machine readable memory in communication with said processor, storing machine-executable virtual machine software controlling operation of said device, said virtual machine software comprising: a parser for receiving a markup language document comprising a single markup language element defining a mathematical operation to be performed upon specified numerical operands; a screen generation engine, for presenting at least one user interface screen at said device in accordance with said markup language document; at least one event handling routine for processing events arising in response either to interaction with said at least one user interface screen or to a message received over a wireless network in accordance with said text file; and at least one object-oriented class corresponding to an action to be performed by said device in response either to said interaction with said at least one screen or to said message received over said wireless network, said action comprising performing said mathematical operation upon said specified numerical operands, wherein said numerical operands are floating point operands and wherein said single markup language element comprises an attribute indicating a desired number of decimal places to be displayed to the right of a decimal point of a floating point result of said mathematical operation, and wherein said performing said mathematical operation comprises rounding a least significant digit of said floating point result that is to be displayed in accordance with said desired number of decimal places based on a value of a most significant digit of said floating point result that is not to be displayed in accordance with said desired number of decimal places. 5. The wireless communication device of claim 4 wherein said markup language is Extensible Markup Language (XML).