1. A handheld electronic device comprising; a processing apparatus comprising a processor; an input apparatus comprising a plurality of input members and being structured to provide input to the processor apparatus, a first set of the input members each having a Roman character assigned thereto, at least some of the input members in the first set of the input members having a first non-Roman character, a second non-Roman character, and a third non-Roman character assigned thereto, wherein said non-Roman characters are from a first language having one or more rules that govern permissible character sequences; an output apparatus structured to received output signals from the processor apparatus; and a memory having stored therein a number of routines which, when executed on the processor, cause the handheld electronic device to be selectively switchable between: (i) a Roman character input mode, and (ii) a non-Roman character input mode, wherein in said Roman character input mode, each said Roman character may be selected and input into said processor apparatus for display on said output apparatus in response to actuation of the input member to which it is assigned, and in said non-Roman character input mode, said processing apparatus determines whether the handheld electronic device is in a shift mode after switching to the non-Roman character input mode, and responsive to determining that the handheld electronic device is not in the shift mode, each first non-Roman character may be selected and input into said processor apparatus for display on said output apparatus in response to a first type of actuation of the input member to which it is assigned, each second non-Roman character may be selected and input into said processor apparatus for display on said output apparatus in response to a second type of actuation of the input member to which it is assigned, wherein upon the second type of actuation of the input member to which it is assigned, the first non-Roman character corresponding to the first type of actuation of the input member to which it is assigned, is displayed and highlighted, prior to the second non-Roman character corresponding to the second type of actuation is displayed, and responsive to determining that handheld electronic device is in the shift mode, each third non-Roman character may be selected and input into said processor apparatus for displaying on said output apparatus in response to a third type of actuation of the input member to which it is assigned, in response to an actuation of a first one of the input members, display on said output apparatus a first one of the non-Roman characters that is assigned to the first one of the input members, and based on said one or more rules that govern permissible character sequences in the first language, prevent display on said output apparatus of a second one of the non-Roman characters in response to an actuation of a second one of the input members having the second one of the non-Roman characters assigned thereto immediately following said actuation of said first one of the input members.