A solution for batch print PDF documents

Dear,

   I use a command line to auto print some PDF documents as below:

   C:\>AcroRd32.exe /h /t PDF_file_name printer_name

   the printing is no problem.

   But when I use the command line to print a large number of PDF files, there are a problem, for example:

   There are 3 PDFs that I want to print, they are 1.pdf, 2.pdf and 3.pdf

   I sent command one by one like below.

  C:\>AcroRd32.exe /h /t 1.pdf printer_name

  C:\>AcroRd32.exe /h /t 2.pdf printer_name

  C:\>AcroRd32.exe /h /t 3.pdf printer_name

  But the hard copy from the print are:

  first print: 1.pdf

  2nd print: 3.pdf

  3rd print:  2.pdf

  what can I do for this case, I want to get the output seq. will be 1.pdf, 2.pdf, 3.pdf.

  Thanks.