How can I print A3 format in SAP

My printer is HP LaserJet 5100
Note I can print ms word document in A3 format but I can't print A3 format in SAP
My output device setting are:
DeviceAttributes:
Device Type = THSAPWIN: MS-Windows-Printer via SAPLPD
Device Class = Standard printer
Access Method:
Host Spool Access Method = S: Print Using SAP Protocol
When I print SM50 output and select format X_65_255, it can print successfully but its format is A4.
What may I do wrong? Please help me how to set up for A3 printing in SAP.
Ps. Do I need to assign A3 format to be default format in that printer?
Is this task for BASIS or ABAP?

Bankly
In printer settings - SPAD - tray info - you can give the Page format for that tray . 
did you try setting that ? Try setting  DINA3.
Liju
Go to START --> SETTINGS ---> Printers
Right click on HP LaserJet 5100 ... Properties..
General Tab --> Printing Preferences --> Advanced --> Paper Size -->
Change it to 14x11 or A3
and
hplaserjet 5100 --> Properties --> Advanced Tab
Printing Defaults --> Advanced --> Paper Size -> change it to 14x11
or A3
hplaserjet 5100 --> Properties --> Device Settings tab -> Autoselect -
-> A3 or 14x11...
PrakashP
Our ABAPer already changed some attributes(ex. font name & size) in print control of SPAD followed by SAP Notes 21738.
Like this ->
# THSAPWIN Z_65_255
# SAPWIN indicatior makes it possible to send via berkeley protocol
\e%SAPWIN%
# change WinCharSet to 222 (Thai)
\eW222;
# set orientation(LANDSCAPE)
#\ePL
# set font name
\eFAngsana New;
# set font size(5.5ponits)->8p->5.5
\eS220
# set vertical spacing(8.7LPI)
#\el3.0;
# set horizontal spacing(24.0CPI)->20->18 (255/11) ->23
#\ec5.0;
# set top/left margin(1.0cm=568.5)
#\eMT567;
#\eML567;
However, it take moderately time to change font size and test report printing for A3 format.
Thank you for your recommend. 

Bankly
I follow by your instruction. It's work well.
Note It doesn't need to setup these config at all.
Tab "Output Attributes"
Paper tray = "Paper tray 3"
Tab "Tray Info"
Tray 3 = "DINA3"
Key points of this solution, If the SAP spool server and the Microsoft Windows spool system are not on the same host, you must create a remote PC connection to the printer and force paper size to be A3 (Prakash's instruction)
By the way, I also adjust HP Laserjet 5100 from "EXEC" to "A3" in Tray 3 physically too. After that I can print ABAP List in A3 Format successfully.