**Exhibit 31.1**

 

**CERTIFICATION OF CHIEF EXECUTIVE OFFICERAS ADOPTED PURSUANT TOSECTION 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.                                       Basedon my knowledge, this report does not contain any untrue statement of materialfact or omit to state a material fact necessary to make the statements made, inlight of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report.

 

3.                                       Based on my knowledge, the financialstatements, and other financial information included in this report, fairlypresent in all material respects the financial condition, results of operationsand cash flows of the registrant as of, and for, the periods presented in thisreport;

 

4.                                       The registrant’s other certifying officer(s)and I are responsible for establishing and maintaining disclosure controls andprocedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) forthe registrant and have:

 

(a)  Designed suchdisclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

 

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

 

(c)  Disclosed in thisreport any change in the registrant’s internal control over financial reportingthat occurred during the registrant’s most recent fiscal quarter (theregistrant’s fourth fiscal quarter in the case of an annual report) that hasmaterially affected, or is reasonably likely to materially affect, theregistrant’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 controlover financial reporting, to the registrant’s auditors and the audit committeeof the registrant’s board of directors (or persons performing the equivalentfunctions):

 

(a)  All significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the registrant’s ability to record, process, summarize and reportfinancial information; and

 

(b)  Any fraud, whetheror not material, that involves management or other employees who have asignificant role in the registrant’s internal control over financial reporting.

 

Date:    August14, 2003

 

 
| By:    | /s/   JAMES T. DEMETRIADES |   |
|--------|--------------------------------------|--------|
| Name:  | James T. Demetriades                 |
| Title: | *Chief  Executive Officer*           |

 

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**CERTIFICATION OF CHIEF FINANCIAL OFFICERAS ADOPTED PURSUANT TOSECTION 302 OF THE SARBANES-OXLEY ACT OF 2002**

 

I, Barry J. Plaga, certifythat:

 

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 financialstatements, and other financial information included in this report, fairlypresent in all material respects the financial condition, results of operationsand cash flows of the registrant as of, and for, the periods presented in thisreport;

 

4.                                       The registrant’s other certifying officer(s)and I are responsible for establishing and maintaining disclosure controls andprocedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) forthe registrant and have:

 

(a)  Designed suchdisclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

 

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

 

(c)  Disclosed in thisreport any change in the registrant’s internal control over financial reportingthat occurred during the registrant’s most recent fiscal quarter (theregistrant’s fourth fiscal quarter in the case of an annual report) that hasmaterially affected, or is reasonably likely to materially affect, theregistrant’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 controlover financial reporting, to the registrant’s auditors and the audit committeeof the registrant’s board of directors (or persons performing the equivalentfunctions): 

 

(a)  All significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the registrant’s ability to record, process, summarize and reportfinancial information; and

 

(b)  Any fraud, whetheror not material, that involves management or other employees who have asignificant role in the registrant’s internal control over financial reporting.

 

 

Date:    August 14, 2003

 

 
| By:    | /s/   BARRY J.  PLAGA |   |
|--------|---------------------------------|--------|
| Name:  | Barry J. Plaga                  |
| Title: | *Chief  Financial Officer*      |

 

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