Thank you for the info Henrik.
I thought HSERIN flushed the buffer first thing - apparently not
I used my pic as a Command Line Editor to communicate from my PC Hyperterminal with many Devices. In the past i did care only for debuging those devices so i never went into trouble looking "why the HECK" those two Bytes pop up into my array and as a result to my Hyperterminal.
Since i have to make a more stable program with many "Command Messages" comming via SMS i tried to debug those two Bytes.
After a lot of search and testing the result was that Hserin [Str Arrayvar\n\c] saves the string until the "c" char received but it doesn't clear the RCREGx after so if Hserin is used again, the last 2 Bytes that remain in the RCREGx become the 2 first received Bytes !

I believe RCREGx is both Readable/Writable register because all the codes bellow worked fine.
Code:
WHILE RC1IF
  Dummy = RCREG1
WEND
Code:
Dummy = RCREG1
Dummy = RCREG1
Code:
RCREG1= 0
RCREG1= 0

Best Regards, Kostas.