Scheduling agreement : BADI/User Exit

Question

Hi All,
I need BADI's or User Exit's for Sheduling Agreement (ME31L) during Creation or Change.
I have tried seraching the Forum, the other Help avaliable, the package, the cl_exithandler debugging method & all. I resulted in writing this thread Question. -- Plz help
In scheduling agreement functionality, Certain validations and checks using user exit or BADI during creation of scheduling agreement should be done.
For Ex: a)No two scheduling agreements should exists in system with combination of
(Material & Vendor document type delivery address for the same validity period)
User Exit should check
b)Items with multiple Tax code should not be allowed in the same SA ,i.e. all SA items should have same tax code
c)Items with multiple Material Number should not be allowed in the same SA     
Please Help me with providing the User Exit's or BADI's for above similar validations. I can Proceed further with Coding.
Thanks& Regards,
Chaitanya L

Answer 1

Please check these & find the appropriate one.
AMPL0001            User subscreen for additional data on AMPL
LMEDR001            Enhancements to print program
LMELA002            Adopt batch no. from shipping notification when posting a GR
LMELA010            Inbound shipping notification: Transfer item data from IDOC
LMEQR001            User exit for source determination
LMEXF001            Conditions in Purchasing Documents Without Invoice Receipt
ME590001            Grouping of requsitions for PO split in ME59
MEETA001            Define schedule line type (backlog, immed. req., preview)
MEFLD004            Determine earliest delivery date f. check w. GR (only PO)
MELAB001            Gen. forecast delivery schedules: Transfer schedule implem.
MEQUERY1            Enhancement to Document Overview ME21N/ME51N
MEVME001            WE default quantity calc. and over/ underdelivery tolerance
MM06E001            User exits for EDI inbound and outbound purchasing documents
MM06E003            Number range and document number
MM06E004            Control import data screens in purchase order
MM06E005            Customer fields in purchasing document
MM06E007            Change document for requisitions upon conversion into PO
MM06E008            Monitoring of contr. target value in case of release orders
MM06E009            Relevant texts for "Texts exist" indicator
MM06E010            Field selection for vendor address
MM06E011            Activate PReq Block
MMAL0001            ALE source list distribution: Outbound processing
MMAL0002            ALE source list distribution: Inbound processing
MMAL0003            ALE purcasing info record distribution: Outbound processing
MMAL0004            ALE purchasing info record distribution: Inbound processing
MMDA0001            Default delivery addresses
MMFAB001            User exit for generation of release order
MRFLB001            Control Items for Contract Release Order
LWSUS001            Customer-Specific Source Determination in Retail
M06B0001            Role determination for purchase requisition release
M06B0002            Changes to comm. structure for purchase requisition release
M06B0003            Number range and document number
M06B0004            Number range and document number
M06B0005            Changes to comm. structure for overall release of requisn.
M06E0004            Changes to communication structure for release purch. doc.
M06E0005            Role determination for release of purchasing documents