**Exhibit31.1**

 

**CERTIFICATION****OF CHIEF EXECUTIVE OFFICER AS ADOPTED PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002**

 

I, James T. Demetriades, certify that:

 

1.  I have reviewed this quarterly report onForm 10-Q of SeeBeyond Technology Corporation.

 

2. Based on my knowledge, this report does notcontain any untrue statement of material fact or omit to state a material factnecessary to make the statements made, in light of the circumstances underwhich such statements were made, not misleading with respect to the periodcovered by this report.

 

3. Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all material respectsthe financial condition, results of operations and cash flows of the registrantas of, and for, the periods presented in this report;

 

4. The registrant’s other certifying officer(s) and I are responsiblefor establishing and maintaining disclosure controls and procedures (as definedin Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant andhave:

 

(a)  Designed such disclosure controls and procedures, or causedsuch disclosure controls and procedures to be designed under our supervision,to ensure that material information relating to the registrant, including itsconsolidated subsidiaries, is made known to us by others within those entities,particularly during the period in which this report is being prepared;

 

(b)  Evaluated the effectiveness of the registrant’s disclosurecontrols and procedures presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures; and

 

(c)  Disclosed in this report any change in the registrant’sinternal control over financial reporting that occurred during the registrant’smost recent fiscal quarter (the registrant’s fourth fiscal quarter in the caseof an annual report) that has materially affected, or is reasonably likely tomaterially affect, the registrant’s internal control over financial reporting;and

 

5. The registrant’s other certifying officer(s) and I have disclosed,based on our most recent evaluation of internal control over financialreporting, to the registrant’s auditors and the audit committee of theregistrant’s board of directors (or persons performing the equivalentfunctions):

 

(a)  All significant deficiencies and material weaknesses in thedesign or operation of internal control over financial reporting which arereasonably likely to adversely affect the registrant’s ability to record,process, summarize and report financial information; and

 

(b)  Any fraud, whether or not material, that involves managementor other employees who have a significant role in the registrant’s internalcontrol over financial reporting.

 
| Date:  | May 7, 2004                          |
|--------|--------------------------------------|
|   |                                 |
|   |                                 |
| By:    | /s/   JAMES T. DEMETRIADES |   |
| Name:  | James T. Demetriades                 |
| Title: | *Chief Executive Officer*            |

 

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**CERTIFICATIONOF CHIEF FINANCIAL OFFICER**

**AS ADOPTEDPURSUANT TO**

**SECTION 302OF THE SARBANES-OXLEY ACT OF 2002**

 

I, Barry J. Plaga, certify that:

 

1.I have reviewed this quarterly report on Form 10-Q of SeeBeyondTechnology Corporation.

 

2.Based on my knowledge, this report does not contain any untruestatement of material fact or omit to state a material fact necessary to makethe statements made, in light of the circumstances under which such statementswere made, not misleading with respect to the period covered by this report.

 

3.Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all material respectsthe financial condition, results of operations and cash flows of the registrantas of, and for, the periods presented in this report;

 

4.The registrant’s other certifying officer(s) and I are responsiblefor establishing and maintaining disclosure controls and procedures (as definedin Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant andhave:

 

(a)  Designed such disclosure controls and procedures, or causedsuch disclosure controls and procedures to be designed under our supervision,to ensure that material information relating to the registrant, including itsconsolidated subsidiaries, is made known to us by others within those entities,particularly during the period in which this report is being prepared;

 

(b)  Evaluated the effectiveness of the registrant’s disclosurecontrols and procedures presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures;

 

(c)  Disclosed in this report any change in the registrant’sinternal control over financial reporting that occurred during the registrant’smost recent fiscal quarter (the registrant’s fourth fiscal quarter in the caseof an annual report) that has materially affected, or is reasonably likely tomaterially affect, the registrant’s internal control over financial reporting;and

 

5.The registrant’s other certifying officer(s) and I have disclosed,based on our most recent evaluation of internal control over financialreporting, to the registrant’s auditors and the audit committee of theregistrant’s board of directors (or persons performing the equivalentfunctions):

 

(a)  All significant deficiencies and material weaknesses in thedesign or operation of internal control over financial reporting which are reasonablylikely to adversely affect the registrant’s ability to record, process,summarize and report financial information; and

 

(b)  Any fraud, whether or not material, that involves managementor other employees who have a significant role in the registrant’s internalcontrol over financial reporting.

 
| Date:  | May 7, 2004                    |
|--------|--------------------------------|
|   |                           |
| By:    | /s/   BARRY J. PLAGA |   |
| Name:  | Barry J. Plaga                 |
| Title: | *Chief Financial Officer*      |

 

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