This proposal will give you 'enter key' instead of emoticon, which goes to new line when hit.
As said before go to settings from SMS app and tool st option item 'soft keyboard'
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Samsung Galaxy S (GT-I9000): ROM KitKat 4.4.2 OmniROM "Mackay" 26-02-14 by kasper_h, modem JV3
LG-P700: ROM KitKat Prime 4.4.2 CM11, by Szymel0
Carrier: Orange France
PC : win 7 + win 8.1
Tablet: Huawei Mediapad 7 / ROM [4.4.2] CM11.0 for Huawei Mediapad 09.03.2014