Exhibit 31.2

CERTIFICATION

|I, Don T. Seaquist, certify   that:
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| | (a) Designed such disclosure   controls and procedures, or caused such disclosure controls and procedures to   be designed under our supervision, to ensure that material information   relating to the registrant, including its consolidated subsidiaries, is made   known to us by others within those entities, particularly during the period   in which this report is being prepared;         
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| | (b) Designed such internal   control over financial reporting, or caused such internal control over   financial reporting to be designed under our supervision, to provide   reasonable assurance regarding the reliability of financial reporting and the   preparation of financial statements for external purposes in accordance with   generally accepted accounting principles;                
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| | (c) Evaluated the   effectiveness of the registrants disclosure controls and procedures and   presented in this report our conclusions about the effectiveness of the   disclosure controls and procedures, as of the end of the period covered by   this report based on such evaluation; and                                                                                                      
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| | (d) Disclosed in this report   any change in the registrants internal control over financial reporting that   occurred during the registrants most recent fiscal quarter (the registrants   fourth fiscal quarter in the case of an annual report) that has materially   affected, or is reasonably likely to materially affect, the registrants   internal control over financial reporting; and

| | 5.     The   registrants other certifying officer and I have disclosed, based on our most   recent evaluation of internal control over financial reporting, to the   registrants auditors and the audit committee of the registrants board of   directors (or persons performing the equivalent functions):
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| | (a) All significant   deficiencies and material weaknesses in the design or operation of internal   control over financial reporting which are reasonably likely to adversely   affect the registrants ability to record, process, summarize and report   financial information; and
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| | (b) Any fraud, whether or not   material, that involves management or other employees who have a significant   role in the registrants internal control over financial reporting.                                                                                                   

|Date: May 8, 2006 |                                             
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|                  | /s/ Don T. Seaquist                         
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|                  | Don T. Seaquist                             
|                  | Vice President, Finance and   Administration

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