Since Hicklin, our courts have followed this rule. See, e.g., Stanfield v. Laccoarce, 284 Or 651, 662, 588 P2d 1271 (1978); Savelich Logging v. Preston Mill Co., 265 Or 456, 465, 509 P2d 1179 (1973); Ziegler v. Bostwick, 106 Or App 666, 669, 809 P2d 131, rev den, 311 Or 644 (1991). In this case, it is undisputed that Stauffer intended to enter satisfaction of judgment as to Lively only and not as to the OCA defendants. Further, the agreement between Stauffer and Lively is specifically described as a "covenant not to execute" and thus fits squarely within the ambit of ORS 31.815, which codified the common-law rule established in Hicklin. Under ORS 31.815, the OCA defendants are liable for the unpaid accrued interest on the judgment because, by its terms, the Stauffer-Lively agreement did not provide for release of the OCA defendants.

OSEA v. Rainier School Dist. No. 13, 311 Or. 188, 194, 808 P.2d 83 (1991). If the agreement is ambiguous, then the trial court erred in granting summary judgment to Deltak. Carlson v. Reservation Ranch, 118 Or. App. 512, 516, 848 P.2d 616 (1993); Ziegler v. Bostwick, 106 Or. App. 666, 668, 809 P.2d 131, rev den 311 Or. 644 (1991). The agreement provides that California law governs its interpretation.

Generally, a dispute concerning that factual question may not be resolved by summary judgment. Pierce v. Mt. Hood Meadows Oregon, Ltd., 118 Or. App. 450, 454, 847 P.2d 909 (1993); Ziegler v. Bostwick, 106 Or. App. 666, 668, 809 P.2d 131, rev den 311 Or. 644 (1991). Therefore, if the trial court was incorrect that the guarantee provision of the Detroit Stoker Agreement is unambiguous, its entry of summary judgment was error.