[Riraito]

here was some code I found in an AddOn a while ago, and used credit to anyone if they reconize it as there own, but it has worked nicely for me:

			<ScrollFrame name="NotePadTextScrollBar" inherits="UIPanelScrollFrameTemplate" virtual="true">
				<Size> <AbsDimension x="310" y="260"/> </Size>
				<Anchors> <Anchor point="BOTTOMLEFT"> <Offset> <AbsDimension x="9.5" y="77"/> </Offset> </Anchor> </Anchors>
				<Layers>			
					<Layer level="ARTWORK">
						<Texture name="$parentTop" file="Interface\PaperDollInfoFrame\UI-Character-ScrollBar">
							<Size> <AbsDimension x="30" y="50"/> </Size>
							<Anchors> <Anchor point="TOP" relativeTo="$parentScrollBarScrollUpButton"> 
								<Offset> <AbsDimension x="0" y="5"/> </Offset> </Anchor> </Anchors>
							<TexCoords left="1" right="1" top="1" bottom="1"/>
						</Texture>
						<Texture file="Interface\PaperDollInfoFrame\UI-Character-ScrollBar">
							<Size> <AbsDimension x="31" y="0"/> </Size>
							<Anchors> <Anchor point="BOTTOM" relativeTo="$parentScrollBarScrollDownButton">
								<Offset> <AbsDimension x="50" y="-2"/> </Offset> </Anchor> </Anchors>
							<TexCoords left="1" right="1" top="1" bottom="1"/>
						</Texture>
					</Layer>			
				</Layers>	
				<ScrollChild>
					<Frame enableMouse="true">
						<Size> <AbsDimension x="280" y="245"/> </Size>
						<Anchors> <Anchor point="TOPLEFT" relativeTo="NotePadMainFrame">
							<Offset> <AbsDimension x="25" y="-185"/> </Offset> </Anchor> </Anchors>
						<Frames>
							<EditBox name="NotesEdit" letters="7500" multiLine="true" enableMouse="true" autoFocus="false">
								<Size> <AbsDimension x="290" y="200"/> </Size>
								<Anchors> <Anchor point="TOPLEFT"> <Offset> <AbsDimension x="15" y="-5"/> </Offset> </Anchor> </Anchors>
								<FontString inherits="QuestFont"/>
								<Scripts>
									<OnShow>
										self:SetFocus()
									</OnShow>									
									<OnClick>
										self:SetFocus()
									</OnClick>
									<OnHide>
										self:ClearFocus()
									</OnHide>
									<OnEscapePressed>
										self:ClearFocus()
									</OnEscapePressed>
									<OnTextChanged>
										NotePad_NotesEdit_OnTextChanged(self)
									</OnTextChanged>
								</Scripts>
							</EditBox>
						</Frames>
					</Frame>
				</ScrollChild>
			</ScrollFrame>

and in the .lua

function NotePad_NotesEdit_OnTextChanged(self)
	local scrollBar = getglobal(self:GetParent():GetParent():GetName().."ScrollBar")
	self:GetParent():GetParent():UpdateScrollChildRect()
	local min, max = scrollBar:GetMinMaxValues()
	if ( max > 0 and (self.max ~= max) and 13 > max-NotePadTextScrollBar:GetVerticalScroll()) then
		self.max = max
		scrollBar:SetValue(max)
	end
	NotePadPVars.notes[NotePadVars.buttonSelected].text = NotesEdit:GetText() -- this is where I save the text
end