Oracle SQL problem determination

Hi, Toadsters:

I'm sure this is not strictly a TOAD question, but I hope that perhaps TOAD (10.6.0.42) can help me solve it.

I have a table that contains, among other things, a date column  PAY_END_DT, and the following PL/SQL to extract from it:

SET SERVEROUTPUT ON;

DECLARE
   begin_period   DATE;
   nbr_periods    NUMBER;
BEGIN
   SELECT MIN(pay_end_dt), COUNT(*)
   INTO   :begin_period, :nbr_periods
   FROM   ps_pay_calendar
   WHERE  company = 'DTC' AND paygroup = 'DCP';
END;

Obviously, the PL/SQL is significantly understated, but this is enough, on our system, to produce this error:

Error at line 3
ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at line 5

To me, this makes zero sense, and I don't know how to diagnose this and make it go away.  Would some kind soul be able to point me in the right direction for this?

Oh!  If I run just that exact SQL (minus the INTO clause of course) I get this:
MIN(PAY_END_DATE) | COUNT(*)
1/16/2011         |       52

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[Description: C:\Documents and Settings\dlovelad.CORP\Application Data\Microsoft\Signatures\Default_files\image004.png]          DTCC Confidential (Yellow)
Dennis Lovelady
813-470-2795
CONNECT... to the future.



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